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Hu Z, Chin Y, Yuan C, Ge Y, Hang Y, Wang D, Yao Q, Hu Y. The luxS deletion reduces the spoilage ability of Shewanella putrefaciens: An analysis focusing on quorum sensing and activated methyl cycle. Food Microbiol 2024; 120:104467. [PMID: 38431319 DOI: 10.1016/j.fm.2024.104467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 01/02/2024] [Accepted: 01/08/2024] [Indexed: 03/05/2024]
Abstract
The luxS mutant strains of Shewanella putrefaciens (SHP) were constructed to investigate the regulations of gene luxS in spoilage ability. The potential regulations of AI-2 quorum sensing (QS) system and activated methyl cycle (AMC) were studied by analyzing the supplementation roles of key circulating substances mediated via luxS, including S-adenosylmethionine (SAM), S-adenosylhomocysteine (SAH), methionine (Met), homocysteine (Hcy) and 4,5-dihydroxy-2,3-pentanedione (DPD). Growth experiments revealed that the luxS deletion led to certain growth limitations of SHP, which were associated with culture medium and exogenous additives. Meanwhile, the decreased biofilm formation and diminished hydrogen sulfide (H2S) production capacity of SHP were observed after luxS deletion. The relatively lower total volatile base nitrogen (TVB-N) contents and higher sensory scores of fish homogenate with luxS mutant strain inoculation also indicated the weaker spoilage-inducing effects after luxS deletion. However, these deficiencies could be offset with the exogenous supply of circulating substances mentioned above. Our findings suggested that the luxS deletion would reduce the spoilage ability of SHP, which was potentially attributed to the disorder of AMC and AI-2 QS system.
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Affiliation(s)
- Zhiheng Hu
- College of Food Science and Engineering, Hainan Tropical Ocean University, Yazhou Bay Innovation Institute, Marine Food Engineering Technology Research Center of Hainan Province, Collaborative Innovation Center of Marine Food Deep Processing, Sanya 572022, China; United Graduate School of Agricultural Sciences, Ueda 3-8-18, Morioka, Iwate 020-8550, Japan
| | - Yaoxian Chin
- College of Food Science and Engineering, Hainan Tropical Ocean University, Yazhou Bay Innovation Institute, Marine Food Engineering Technology Research Center of Hainan Province, Collaborative Innovation Center of Marine Food Deep Processing, Sanya 572022, China
| | - Chunhong Yuan
- Faculty of Agriculture, Iwate University, Ueda 3-8-18, Morioka, Iwate 020-8550, Japan; Agri-Innovation Center, Iwate University, Ueda 3-8-18, Morioka, Iwate 020-8550, Japan
| | - Yingliang Ge
- College of Food Science and Engineering, Hainan Tropical Ocean University, Yazhou Bay Innovation Institute, Marine Food Engineering Technology Research Center of Hainan Province, Collaborative Innovation Center of Marine Food Deep Processing, Sanya 572022, China
| | - Yuyu Hang
- College of Food Science and Engineering, Hainan Tropical Ocean University, Yazhou Bay Innovation Institute, Marine Food Engineering Technology Research Center of Hainan Province, Collaborative Innovation Center of Marine Food Deep Processing, Sanya 572022, China
| | - Dongxue Wang
- College of Food Science and Engineering, Hainan Tropical Ocean University, Yazhou Bay Innovation Institute, Marine Food Engineering Technology Research Center of Hainan Province, Collaborative Innovation Center of Marine Food Deep Processing, Sanya 572022, China
| | - Qian Yao
- Key Laboratory of Medicinal and Edible Plants Resources Development of Sichuan Education Department, Sichuan Industrial Institute of Antibiotics, School of Pharmacy, Chengdu University, Chengdu 610106, China
| | - Yaqin Hu
- College of Food Science and Engineering, Hainan Tropical Ocean University, Yazhou Bay Innovation Institute, Marine Food Engineering Technology Research Center of Hainan Province, Collaborative Innovation Center of Marine Food Deep Processing, Sanya 572022, China.
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Mohammed V, Arockiaraj J. Unveiling the trifecta of cyanobacterial quorum sensing: LuxI, LuxR and LuxS as the intricate machinery for harmful algal bloom formation in freshwater ecosystems. Sci Total Environ 2024; 924:171644. [PMID: 38471587 DOI: 10.1016/j.scitotenv.2024.171644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Revised: 02/22/2024] [Accepted: 03/09/2024] [Indexed: 03/14/2024]
Abstract
Harmful algal blooms (HABs) are causing significant disruptions in freshwater ecosystems, primarily due to the proliferation of cyanobacteria. These blooms have a widespread impact on various lakes globally, leading to profound environmental and health consequences. Cyanobacteria, with their ability to produce diverse toxins, pose a particular concern as they negatively affect the well-being of humans and animals, exacerbating the situation. Notably, cyanobacteria utilize quorum sensing (QS) as a complex communication mechanism that facilitates coordinated growth and toxin production. QS plays a critical role in regulating the dynamics of HABs. However, recent advances in control and mitigation strategies have shown promising results in effectively managing and reducing the occurrence of HABs. This comprehensive review explores the intricate aspects of cyanobacteria development in freshwater ecosystems, explicitly focusing on deciphering the signaling molecules associated with QS and their corresponding genes. Furthermore, a concise overview of diverse measures implemented to efficiently control and mitigate the spread of these bacteria will be provided, shedding light on the ongoing global efforts to address this urgent environmental issue. By deepening our understanding of the mechanisms driving cyanobacteria growth and developing targeted control strategies, we hope to safeguard freshwater ecosystems and protect the health of humans and animals from the detrimental impacts of HABs.
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Affiliation(s)
- Vajagathali Mohammed
- Department of Forensic Science, Yenepoya Institute of Arts, Science, Commerce, and Management, Yenepoya (Deemed to be University), Mangaluru 575013, Karnataka, India
| | - Jesu Arockiaraj
- Toxicology and Pharmacology Laboratory, Department of Biotechnology, Faculty of Science and Humanities, SRM Institute of Science and Technology, Kattankulathur 603203, Chengalpattu District, Tamil Nadu, India.
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Sprenger M, Siemers M, Krautwurst S, Papenfort K. Small RNAs direct attack and defense mechanisms in a quorum sensing phage and its host. Cell Host Microbe 2024; 32:727-738.e6. [PMID: 38579715 DOI: 10.1016/j.chom.2024.03.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Revised: 02/02/2024] [Accepted: 03/13/2024] [Indexed: 04/07/2024]
Abstract
Many, if not all, bacteria use quorum sensing (QS) to control collective behaviors, and more recently, QS has also been discovered in bacteriophages (phages). Phages can produce communication molecules of their own, or "listen in" on the host's communication processes, to switch between lytic and lysogenic modes of infection. Here, we study the interaction of Vibrio cholerae with the lysogenic phage VP882, which is activated by the QS molecule DPO. We discover that induction of VP882 results in the binding of phage transcripts to the major RNA chaperone Hfq, which in turn outcompetes and downregulates host-encoded small RNAs (sRNAs). VP882 itself also encodes Hfq-binding sRNAs, and we demonstrate that one of these sRNAs, named VpdS, promotes phage replication by regulating host and phage mRNA levels. We further show that host-encoded sRNAs can antagonize phage replication by downregulating phage mRNA expression and thus might be part of the host's phage defense arsenal.
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Affiliation(s)
- Marcel Sprenger
- Friedrich Schiller University, Institute of Microbiology, 07745 Jena, Germany
| | - Malte Siemers
- Friedrich Schiller University, Institute of Microbiology, 07745 Jena, Germany; Microverse Cluster, Friedrich Schiller University Jena, 07743 Jena, Germany
| | | | - Kai Papenfort
- Friedrich Schiller University, Institute of Microbiology, 07745 Jena, Germany; Microverse Cluster, Friedrich Schiller University Jena, 07743 Jena, Germany.
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de la Fuente I, Manzano-Morales S, Sanz D, Prieto A, Barriuso J. Quorum sensing in bacteria: in silico protein analysis, ecophysiology, and reconstruction of their evolutionary history. BMC Genomics 2024; 25:441. [PMID: 38702600 PMCID: PMC11069264 DOI: 10.1186/s12864-024-10355-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Accepted: 04/25/2024] [Indexed: 05/06/2024] Open
Abstract
BACKGROUND Quorum sensing (QS) is a sophisticated cell-to-cell signalling mechanism that allows the coordination of important processes in microbial populations. The AI-1 and AI-2 autoinducer systems are among the best characterized bacterial QS systems at the genetic level. RESULTS In this study, we present data derived from in silico screening of QS proteins from bacterial genomes available in public databases. Sequence analyses allowed identifying candidate sequences of known QS systems that were used to build phylogenetic trees. Eight categories were established according to the number of genes from the two major QS systems present in each genome, revealing a correlation with specific taxa, lifestyles or metabolic traits. Many species had incomplete QS systems, encoding the receptor protein but not the biosynthesis of the quorum sensing molecule (QSMs). Reconstruction of the evolutionary history of the LuxR family and prediction of the 3D structure of the ancestral protein suggested their monomeric configuration in the absence of the signal molecule and the presence of a cavity for its binding. CONCLUSIONS Here we correlate the taxonomic affiliation and lifestyle of bacteria from different genera with the QS systems encoded in their genomes. Moreover, we present the first ancestral reconstruction of the LuxR QS receptors, providing further insight in their evolutionary history.
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Affiliation(s)
- Iñigo de la Fuente
- Centro de Investigaciones Biológicas (CIB Margarita Salas), Department of Microbial and Plant Biotechnology, Consejo Superior de Investigaciones Científicas (CSIC), Ramiro de Maeztu 9, Madrid, 28040, Spain
| | - Saioa Manzano-Morales
- Centro de Investigaciones Biológicas (CIB Margarita Salas), Department of Microbial and Plant Biotechnology, Consejo Superior de Investigaciones Científicas (CSIC), Ramiro de Maeztu 9, Madrid, 28040, Spain
| | - David Sanz
- Centro de Investigaciones Biológicas (CIB Margarita Salas), Department of Microbial and Plant Biotechnology, Consejo Superior de Investigaciones Científicas (CSIC), Ramiro de Maeztu 9, Madrid, 28040, Spain
| | - Alicia Prieto
- Centro de Investigaciones Biológicas (CIB Margarita Salas), Department of Microbial and Plant Biotechnology, Consejo Superior de Investigaciones Científicas (CSIC), Ramiro de Maeztu 9, Madrid, 28040, Spain
| | - Jorge Barriuso
- Centro de Investigaciones Biológicas (CIB Margarita Salas), Department of Microbial and Plant Biotechnology, Consejo Superior de Investigaciones Científicas (CSIC), Ramiro de Maeztu 9, Madrid, 28040, Spain.
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Podkowik M, Perault AI, Putzel G, Pountain A, Kim J, DuMont AL, Zwack EE, Ulrich RJ, Karagounis TK, Zhou C, Haag AF, Shenderovich J, Wasserman GA, Kwon J, Chen J, Richardson AR, Weiser JN, Nowosad CR, Lun DS, Parker D, Pironti A, Zhao X, Drlica K, Yanai I, Torres VJ, Shopsin B. Quorum-sensing agr system of Staphylococcus aureus primes gene expression for protection from lethal oxidative stress. eLife 2024; 12:RP89098. [PMID: 38687677 PMCID: PMC11060713 DOI: 10.7554/elife.89098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/02/2024] Open
Abstract
The agr quorum-sensing system links Staphylococcus aureus metabolism to virulence, in part by increasing bacterial survival during exposure to lethal concentrations of H2O2, a crucial host defense against S. aureus. We now report that protection by agr surprisingly extends beyond post-exponential growth to the exit from stationary phase when the agr system is no longer turned on. Thus, agr can be considered a constitutive protective factor. Deletion of agr resulted in decreased ATP levels and growth, despite increased rates of respiration or fermentation at appropriate oxygen tensions, suggesting that Δagr cells undergo a shift towards a hyperactive metabolic state in response to diminished metabolic efficiency. As expected from increased respiratory gene expression, reactive oxygen species (ROS) accumulated more in the agr mutant than in wild-type cells, thereby explaining elevated susceptibility of Δagr strains to lethal H2O2 doses. Increased survival of wild-type agr cells during H2O2 exposure required sodA, which detoxifies superoxide. Additionally, pretreatment of S. aureus with respiration-reducing menadione protected Δagr cells from killing by H2O2. Thus, genetic deletion and pharmacologic experiments indicate that agr helps control endogenous ROS, thereby providing resilience against exogenous ROS. The long-lived 'memory' of agr-mediated protection, which is uncoupled from agr activation kinetics, increased hematogenous dissemination to certain tissues during sepsis in ROS-producing, wild-type mice but not ROS-deficient (Cybb-/-) mice. These results demonstrate the importance of protection that anticipates impending ROS-mediated immune attack. The ubiquity of quorum sensing suggests that it protects many bacterial species from oxidative damage.
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Affiliation(s)
- Magdalena Podkowik
- Department of Medicine, Division of Infectious Diseases, NYU Grossman School of MedicineNew YorkUnited States
- Antimicrobial-Resistant Pathogens Program, New York University School of MedicineNew YorkUnited States
| | - Andrew I Perault
- Antimicrobial-Resistant Pathogens Program, New York University School of MedicineNew YorkUnited States
- Department of Microbiology, NYU Grossman School of MedicineNew YorkUnited States
| | - Gregory Putzel
- Antimicrobial-Resistant Pathogens Program, New York University School of MedicineNew YorkUnited States
- Department of Microbiology, NYU Grossman School of MedicineNew YorkUnited States
- Microbial Computational Genomic Core Lab, NYU Grossman School of MedicineNew YorkUnited States
| | - Andrew Pountain
- Institute for Systems Genetics; NYU Grossman School of MedicineNew YorkUnited States
| | - Jisun Kim
- Department of Pathology, Immunology and Laboratory Medicine, Center for Immunity and Inflammation, Rutgers New Jersey Medical SchoolNewarkUnited States
| | - Ashley L DuMont
- Department of Medicine, Division of Infectious Diseases, NYU Grossman School of MedicineNew YorkUnited States
| | - Erin E Zwack
- Department of Microbiology, NYU Grossman School of MedicineNew YorkUnited States
| | - Robert J Ulrich
- Department of Medicine, Division of Infectious Diseases, NYU Grossman School of MedicineNew YorkUnited States
| | - Theodora K Karagounis
- Antimicrobial-Resistant Pathogens Program, New York University School of MedicineNew YorkUnited States
- Ronald O. Perelman Department of Dermatology; NYU Grossman School of MedicineNew YorkUnited States
| | - Chunyi Zhou
- Department of Medicine, Division of Infectious Diseases, NYU Grossman School of MedicineNew YorkUnited States
- Antimicrobial-Resistant Pathogens Program, New York University School of MedicineNew YorkUnited States
| | - Andreas F Haag
- School of Medicine, University of St AndrewsSt AndrewsUnited Kingdom
| | - Julia Shenderovich
- Antimicrobial-Resistant Pathogens Program, New York University School of MedicineNew YorkUnited States
- Department of Microbiology, NYU Grossman School of MedicineNew YorkUnited States
| | - Gregory A Wasserman
- Department of Surgery, Northwell Health Lenox Hill HospitalNew YorkUnited States
| | - Junbeom Kwon
- Department of Medicine, Division of Infectious Diseases, NYU Grossman School of MedicineNew YorkUnited States
| | - John Chen
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of SingaporeSingaporeSingapore
| | - Anthony R Richardson
- Department of Microbiology and Molecular Genetics, University of PittsburghPittsburghUnited States
| | - Jeffrey N Weiser
- Department of Microbiology, NYU Grossman School of MedicineNew YorkUnited States
| | - Carla R Nowosad
- Department of Pathology, NYU Grossman School of MedicineNew YorkUnited States
| | - Desmond S Lun
- Center for Computational and Integrative Biology and Department of Computer Science, Rutgers UniversityCamdenUnited States
| | - Dane Parker
- Department of Pathology, Immunology and Laboratory Medicine, Center for Immunity and Inflammation, Rutgers New Jersey Medical SchoolNewarkUnited States
| | - Alejandro Pironti
- Antimicrobial-Resistant Pathogens Program, New York University School of MedicineNew YorkUnited States
- Department of Microbiology, NYU Grossman School of MedicineNew YorkUnited States
- Microbial Computational Genomic Core Lab, NYU Grossman School of MedicineNew YorkUnited States
| | - Xilin Zhao
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen UniversityXiamenChina
| | - Karl Drlica
- Public Health Research Institute, New Jersey Medical School, Rutgers UniversityNew YprkUnited States
- Department of Microbiology, Biochemistry & Molecular Genetics, New Jersey Medical School, Rutgers UniversityNewarkUnited States
| | - Itai Yanai
- Institute for Systems Genetics; NYU Grossman School of MedicineNew YorkUnited States
- Department of Biochemistry and Molecular Pharmacology, NYU Grossman School of MedicineNew YorkUnited States
| | - Victor J Torres
- Antimicrobial-Resistant Pathogens Program, New York University School of MedicineNew YorkUnited States
- Department of Microbiology, NYU Grossman School of MedicineNew YorkUnited States
| | - Bo Shopsin
- Department of Medicine, Division of Infectious Diseases, NYU Grossman School of MedicineNew YorkUnited States
- Antimicrobial-Resistant Pathogens Program, New York University School of MedicineNew YorkUnited States
- Department of Microbiology, NYU Grossman School of MedicineNew YorkUnited States
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Jiang B, Qiu H, Lu C, Lu M, Li Y, Dai W. Uncovering the GacS-mediated role in evolutionary progression through trajectory reconstruction in Pseudomonas aeruginosa. Nucleic Acids Res 2024; 52:3856-3869. [PMID: 38477346 DOI: 10.1093/nar/gkae187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Revised: 02/23/2024] [Accepted: 03/05/2024] [Indexed: 03/14/2024] Open
Abstract
The genetic diversities of subpopulations drive the evolution of pathogens and affect their ability to infect hosts and cause diseases. However, most studies to date have focused on the identification and characterization of adaptive mutations in single colonies, which do not accurately reflect the phenotypes of an entire population. Here, to identify the composition of variant subpopulations within a pathogen population, we developed a streamlined approach that combines high-throughput sequencing of the entire population cells with genotyping of single colonies. Using this method, we reconstructed a detailed quorum-sensing (QS) evolutionary trajectory in Pseudomonas aeruginosa. Our results revealed a new adaptive mutation in the gacS gene, which codes for a histidine kinase sensor of a two-component system (TCS), during QS evolution. This mutation reduced QS activity, allowing the variant to sweep throughout the whole population, while still being vulnerable to invasion by the emerging QS master regulator LasR-null mutants. By tracking the evolutionary trajectory, we found that mutations in gacS facilitated QS-rewiring in the LasR-null mutant. This rapid QS revertant caused by inactive GacS was found to be associated with the promotion of ribosome biogenesis and accompanied by a trade-off of reduced bacterial virulence on host cells. In conclusion, our findings highlight the crucial role of the global regulator GacS in modulating the progression of QS evolution and the virulence of the pathogen population.
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Affiliation(s)
- Bo Jiang
- Integrative Microbiology Research Center, College of Plant Protection, South China Agricultural University, Guangzhou 510642, China
| | - Huifang Qiu
- Integrative Microbiology Research Center, College of Plant Protection, South China Agricultural University, Guangzhou 510642, China
| | - Chenghui Lu
- Integrative Microbiology Research Center, College of Plant Protection, South China Agricultural University, Guangzhou 510642, China
| | - Mingqi Lu
- Integrative Microbiology Research Center, College of Plant Protection, South China Agricultural University, Guangzhou 510642, China
| | - Yuanhao Li
- Integrative Microbiology Research Center, College of Plant Protection, South China Agricultural University, Guangzhou 510642, China
| | - Weijun Dai
- Integrative Microbiology Research Center, College of Plant Protection, South China Agricultural University, Guangzhou 510642, China
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Chan YL, Chee CF, Tang SN, Tay ST. Unveilling genetic profiles and correlations of biofilm-associated genes, quorum sensing, and antibiotic resistance in Staphylococcus aureus isolated from a Malaysian Teaching Hospital. Eur J Med Res 2024; 29:246. [PMID: 38649897 PMCID: PMC11036768 DOI: 10.1186/s40001-024-01831-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2023] [Accepted: 04/05/2024] [Indexed: 04/25/2024] Open
Abstract
BACKGROUND Staphylococcus aureus is a notorious multidrug resistant pathogen prevalent in healthcare facilities worldwide. Unveiling the mechanisms underlying biofilm formation, quorum sensing and antibiotic resistance can help in developing more effective therapy for S. aureus infection. There is a scarcity of literature addressing the genetic profiles and correlations of biofilm-associated genes, quorum sensing, and antibiotic resistance among S. aureus isolates from Malaysia. METHODS Biofilm and slime production of 68 methicillin-susceptible S. aureus (MSSA) and 54 methicillin-resistant (MRSA) isolates were determined using a a plate-based crystal violet assay and Congo Red agar method, respectively. The minimum inhibitory concentration values against 14 antibiotics were determined using VITEK® AST-GP67 cards and interpreted according to CLSI-M100 guidelines. Genetic profiling of 11 S. aureus biofilm-associated genes and agr/sar quorum sensing genes was performed using single or multiplex polymerase chain reaction (PCR) assays. RESULTS In this study, 75.9% (n = 41) of MRSA and 83.8% (n = 57) of MSSA isolates showed strong biofilm-forming capabilities. Intermediate slime production was detected in approximately 70% of the isolates. Compared to MSSA, significantly higher resistance of clindamycin, erythromycin, and fluoroquinolones was noted among the MRSA isolates. The presence of intracellular adhesion A (icaA) gene was detected in all S. aureus isolates. All MSSA isolates harbored the laminin-binding protein (eno) gene, while all MRSA isolates harbored intracellular adhesion D (icaD), clumping factors A and B (clfA and clfB) genes. The presence of agrI and elastin-binding protein (ebpS) genes was significantly associated with biofilm production in MSSA and MRSA isolates, respectively. In addition, agrI gene was also significantly correlated with oxacillin, cefoxitin, and fluoroquinolone resistance. CONCLUSIONS The high prevalence of biofilm and slime production among MSSA and MRSA isolates correlates well with the detection of a high prevalence of biofilm-associated genes and agr quorum sensing system. A significant association of agrI gene was found with cefoxitin, oxacillin, and fluoroquinolone resistance. A more focused approach targeting biofilm-associated and quorum sensing genes is important in developing new surveillance and treatment strategies against S. aureus biofilm infection.
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Affiliation(s)
- Yun Li Chan
- Department of Medical Microbiology, Faculty of Medicine, Universiti Malaya, 50603, Kuala Lumpur, Malaysia
| | - Chin Fei Chee
- Nanotechnology and Catalysis Research Centre, Universiti Malaya, 50603, Kuala Lumpur, Malaysia
| | - Soo Nee Tang
- Department of Medical Microbiology, Faculty of Medicine, Universiti Malaya, 50603, Kuala Lumpur, Malaysia.
| | - Sun Tee Tay
- Department of Medical Microbiology, Faculty of Medicine, Universiti Malaya, 50603, Kuala Lumpur, Malaysia.
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Talaat R, Abu El-Naga MN, El-Bialy HAA, El-Fouly MZ, Abouzeid MA. Quenching of quorum sensing in multi-drug resistant Pseudomonas aeruginosa: insights on halo-bacterial metabolites and gamma irradiation as channels inhibitors. Ann Clin Microbiol Antimicrob 2024; 23:31. [PMID: 38600513 PMCID: PMC11007959 DOI: 10.1186/s12941-024-00684-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Accepted: 03/03/2024] [Indexed: 04/12/2024] Open
Abstract
BACKGROUND Anti-virulence therapy is a promising strategy to treat multi-drug resistant (MDR) pathogens. Pseudomonas aeruginosa is a potent opportunistic pathogen because of an array of virulence factors that are regulated by quorum sensing systems. METHODS The virulence features of four multi-drug resistant P. aeruginosa strains were investigated upon exposure to the sub-lethal dose of gamma rays (1 kGy), and sub-inhibitory concentrations of bioactive metabolites recovered from local halophilic strains in comparison to control. Then, the gene expression of AHL-mediated quorum sensing systems (las/rhl) was quantitatively determined in treated and untreated groups by real-time PCR. RESULTS The bioactive metabolites recovered from halophilic strains previously isolated from saline ecosystems were identified as Halomonas cupida (Halo-Rt1), H. elongate (Halo-Rt2), Vigibacillus natechei (Halo-Rt3), Sediminibacillus terrae (Halo-Rt4) and H. almeriensis (Halo-Rt5). Results revealed that both gamma irradiation and bioactive metabolites significantly reduced the virulence factors of the tested MDR strains. The bioactive metabolites showed a maximum efficiency for inhibiting biofilm formation and rhamnolipids production whereas the gamma irradiation succeeded in decreasing other virulence factors to lower levels in comparison to control. Quantitative-PCR results showed that AHL-mediated quorum sensing systems (las/rhl) in P. aeruginosa strains were downregulated either by halo-bacterial metabolites or gamma irradiation in all treatments except the upregulation of both lasI internal gene and rhlR intact gene in P. aeruginosa NCR-RT3 and both rhlI internal gene and rhlR intact gene in P. aeruginosa U3 by nearly two folds or more upon exposure to gamma irradiation. The most potent result was observed in the expression of lasI internal gene that was downregulated by more than ninety folds in P. aeruginosa NCR-RT2 after treatment with metabolites of S. terrae (Halo-Rt4). Analyzing metabolites recovered from H. cupida (Halo-Rt1) and H. elongate (Halo-Rt2) using LC-ESI-MS/MS revealed many chemical compounds that have quorum quenching properties including glabrol, 5,8-dimethoxyquinoline-2-carbaldehyde, linoleoyl ethanolamide, agelasine, penigequinolones derivatives, berberine, tetracosanoic acid, and liquidambaric lactone in the former halophile and phloretin, lycoctonine, fucoxanthin, and crassicauline A in the latter one. CONCLUSION QS inhibitors can significantly reduce the pathogenicity of MDR P. aeruginosa strains; and thus can be an effective and successful strategy for treating antibiotic resistant traits.
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Affiliation(s)
- Reham Talaat
- Radiation Microbiology Department, National Center for Radiation Research and Technology (NCRRT), Egyptian Atomic Energy Authority (EAEA), Cairo, Egypt
| | - Mohamed N Abu El-Naga
- Radiation Microbiology Department, National Center for Radiation Research and Technology (NCRRT), Egyptian Atomic Energy Authority (EAEA), Cairo, Egypt
| | - Heba Abd Alla El-Bialy
- Radiation Microbiology Department, National Center for Radiation Research and Technology (NCRRT), Egyptian Atomic Energy Authority (EAEA), Cairo, Egypt.
| | - Mohie Z El-Fouly
- Radiation Microbiology Department, National Center for Radiation Research and Technology (NCRRT), Egyptian Atomic Energy Authority (EAEA), Cairo, Egypt
| | - Mohamed A Abouzeid
- Microbiology Department, Faculty of Science, Ain Shams University, Cairo, Egypt
- Faculty of Science, Galala University, Suez, Egypt
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Ortiz J, Dias N, Alvarado R, Soto J, Sanhueza T, Rabert C, Jorquera M, Arriagada C. N- acyl homoserine lactones (AHLs) type signal molecules produced by rhizobacteria associated with plants that growing in a metal(oids) contaminated soil: A catalyst for plant growth. Microbiol Res 2024; 281:127606. [PMID: 38277718 DOI: 10.1016/j.micres.2024.127606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Revised: 11/23/2023] [Accepted: 01/08/2024] [Indexed: 01/28/2024]
Abstract
The present study explores the potential of rhizobacteria isolated from Baccharis linearis and Solidago chilensis in metal(loid)-contaminated soil for producing N-acyl-homoserine lactones (AHLs)-type signal molecules and promoting plant growth. A total of 42 strains were isolated, four demonstrating the production of AHL-type signal molecules. Based on 16S rRNA gene sequencing analyses and MALDI-TOF analyses, these four isolates were identified as belonging to the Pseudomonas genus, specifically P. brassicacearum, P. frederickberguensis, P. koreensis, and P. orientalis. The four AHL-producing strains were evaluated for metal(loid)s tolerance, their plant growth promotion traits, AHL quantification, and their impact on in vitro Lactuca sativa plant growth. The study found that four strains exhibited high tolerance to metal(loid)s, particularly As, Cu, and Zn. Additionally, plant growth-promoting traits were detected in AHL-producing bacteria, such as siderophore production, ammonia production, ACC deaminase activity, and P solubilization. Notably, AHL production varied among strains isolated from B. linearis, where C7-HSL and C9-HSL signal molecules were detected, and S. chilensis, where only C7-HSL signal molecules were observed. In the presence of copper, the production of C7-HSL and C9-HSL significantly decreased in B. linearis isolates, while in S. chilensis isolates, C7-HSL production was inhibited. Further, when these strains were inoculated on lettuce seeds and in vitro plants, a significant increase in germination and plant growth was observed. Mainly, the inoculation of P. brassicacearum and P. frederickberguensis led to extensive root hair development, significantly increasing length and root dry weight. Our results demonstrate that rhizospheric strains produce AHL molecules and stimulate plant growth, primarily through root development. However, the presence of copper reduces the production of these molecules, potentially affecting the root development of non-metalloid tolerant plants such as S. chilensis, which would explain its low population in this hostile environment.
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Affiliation(s)
- Javier Ortiz
- Laboratorio de Biorremediación, Facultad de Ciencias Agropecuarias y Mediambiente, Universidad de La Frontera, Temuco, Chile
| | - Nathalia Dias
- Scientific and Technological Bioresource Nucleus (BIOREN), Universidad de La Frontera, Temuco, Chile
| | - Roxana Alvarado
- Laboratorio de Biorremediación, Facultad de Ciencias Agropecuarias y Mediambiente, Universidad de La Frontera, Temuco, Chile
| | - Javiera Soto
- Laboratorio de Biorremediación, Facultad de Ciencias Agropecuarias y Mediambiente, Universidad de La Frontera, Temuco, Chile
| | - Tedy Sanhueza
- Laboratorio de Biorremediación, Facultad de Ciencias Agropecuarias y Mediambiente, Universidad de La Frontera, Temuco, Chile
| | - Claudia Rabert
- Instituto de Ciencias Biomédicas, Facultad de Ciencias de la Salud, Universidad Autónoma de Chile, Temuco, Chile
| | - Milko Jorquera
- Laboratorio de Ecología Microbiana Aplicada (EMALAB), Departamento de Ciencias Químicas y Recursos Naturales, Universidad de La Frontera, Temuco, Chile
| | - César Arriagada
- Laboratorio de Biorremediación, Facultad de Ciencias Agropecuarias y Mediambiente, Universidad de La Frontera, Temuco, Chile.
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10
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Gifford DR, Bhattacharyya A, Geim A, Marshall E, Krašovec R, Knight CG. Environmental and genetic influence on the rate and spectrum of spontaneous mutations in Escherichia coli. Microbiology (Reading) 2024; 170:001452. [PMID: 38687010 PMCID: PMC11084559 DOI: 10.1099/mic.0.001452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Accepted: 03/19/2024] [Indexed: 05/02/2024]
Abstract
Spontaneous mutations are the ultimate source of novel genetic variation on which evolution operates. Although mutation rate is often discussed as a single parameter in evolution, it comprises multiple distinct types of changes at the level of DNA. Moreover, the rates of these distinct changes can be independently influenced by genomic background and environmental conditions. Using fluctuation tests, we characterized the spectrum of spontaneous mutations in Escherichia coli grown in low and high glucose environments. These conditions are known to affect the rate of spontaneous mutation in wild-type MG1655, but not in a ΔluxS deletant strain - a gene with roles in both quorum sensing and the recycling of methylation products used in E. coli's DNA repair process. We find an increase in AT>GC transitions in the low glucose environment, suggesting that processes relating to the production or repair of this mutation could drive the response of overall mutation rate to glucose concentration. Interestingly, this increase in AT>GC transitions is maintained by the glucose non-responsive ΔluxS deletant. Instead, an elevated rate of GC>TA transversions, more common in a high glucose environment, leads to a net non-responsiveness of overall mutation rate for this strain. Our results show how relatively subtle changes, such as the concentration of a carbon substrate or loss of a regulatory gene, can substantially influence the amount and nature of genetic variation available to selection.
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Affiliation(s)
- Danna R. Gifford
- Division of Evolution, Infection and Genomics, School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK
| | - Anish Bhattacharyya
- Division of Evolution, Infection and Genomics, School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK
| | - Alexandra Geim
- Division of Evolution, Infection and Genomics, School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK
- Pembroke College, University of Cambridge, Cambridge, UK
| | - Eleanor Marshall
- Division of Evolution, Infection and Genomics, School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK
| | - Rok Krašovec
- Division of Evolution, Infection and Genomics, School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK
| | - Christopher G. Knight
- Department of Earth and Environmental Sciences, School of Natural Sciences, Faculty of Science and Engineering, The University of Manchester, Manchester, UK
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Hemmati J, Nazari M, Abolhasani FS, Ahmadi A, Asghari B. In vitro investigation of relationship between quorum-sensing system genes, biofilm forming ability, and drug resistance in clinical isolates of Pseudomonas aeruginosa. BMC Microbiol 2024; 24:99. [PMID: 38528442 DOI: 10.1186/s12866-024-03249-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Accepted: 03/04/2024] [Indexed: 03/27/2024] Open
Abstract
BACKGROUND Pseudomonas aeruginosa is an opportunistic pathogen in the health-care systems and one of the primary causative agents with high mortality in hospitalized patients, particularly immunocompromised. The limitation of effective antibiotic administration in multidrug-resistant and extensively drug-resistant P. aeruginosa isolates leads to the development of nosocomial infections and health problems. Quorum sensing system contributes to biofilm formation, expression of bacterial virulence factors, and development of drug resistance, causing prolonged patient infections. Therefore, due to the significance of the quorum sensing system in increasing the pathogenicity of P. aeruginosa, the primary objective of our study was to investigate the frequency of quorum sensing genes, as well as the biofilm formation and antibiotic resistance pattern among P. aeruginosa strains. METHODS A total of 120 P. aeruginosa isolates were collected from different clinical specimens. The disk diffusion method was applied to detect the antibiotic resistance pattern of P. aeruginosa strains. Also, the microtiter plate method was carried out to evaluate the biofilm-forming ability of isolates. Finally, the frequency of rhlI, rhlR, lasI, and lasR genes was examined by the polymerase chain reaction method. RESULTS In total, 88.3% P. aeruginosa isolates were found to be multidrug-resistant, of which 30.1% had extensively drug-resistant pattern. The highest and lowest resistance rates were found against ceftazidime (75.0%) and ciprofloxacin (46.6%), respectively. Also, 95.8% of isolates were able to produce biofilm, of which 42.5%, 33.3%, and 20.0% had strong, moderate, and weak biofilm patterns, respectively. The frequency of quorum sensing genes among all examined strains was as follows: rhlI (81.6%), rhlR (90.8%), lasI (89.1%), and lasR (78.3%). The most common type of quorum sensing genes among multidrug-resistant isolates were related to rhlR and lasI genes with 94.3%. Furthermore, rhlI, rhlR, and lasI genes were positive for all extensively drug-resistant isolates. However, the lasR gene had the lowest frequency among both multidrug-resistant (83.0%) and extensively drug-resistant (90.6%) isolates. Moreover, rhlR (94.7%) and lasR (81.7%) genes had the highest and lowest prevalence among biofilm-forming isolates, respectively. CONCLUSION Our findings disclosed the significantly high prevalence of drug resistance among P. aeruginosa isolates. Also, the quorum sensing system had a significant correlation with biofilm formation and drug resistance, indicating the essential role of this system in the emergence of nosocomial infections caused by P. aeruginosa.
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Affiliation(s)
- Jaber Hemmati
- Student Research Committee, Hamadan University of Medical Sciences, Hamadan, Iran
- Department of Microbiology, School of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Mohsen Nazari
- Student Research Committee, Hamadan University of Medical Sciences, Hamadan, Iran
- Department of Microbiology, School of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Fatemeh Sadat Abolhasani
- Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Amjad Ahmadi
- Student Research Committee, Hamadan University of Medical Sciences, Hamadan, Iran.
- Department of Microbiology, School of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran.
| | - Babak Asghari
- Department of Microbiology, School of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran.
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12
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Aboelnaga N, Elsayed SW, Abdelsalam NA, Salem S, Saif NA, Elsayed M, Ayman S, Nasr M, Elhadidy M. Deciphering the dynamics of methicillin-resistant Staphylococcus aureus biofilm formation: from molecular signaling to nanotherapeutic advances. Cell Commun Signal 2024; 22:188. [PMID: 38519959 PMCID: PMC10958940 DOI: 10.1186/s12964-024-01511-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Accepted: 02/01/2024] [Indexed: 03/25/2024] Open
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) represents a global threat, necessitating the development of effective solutions to combat this emerging superbug. In response to selective pressures within healthcare, community, and livestock settings, MRSA has evolved increased biofilm formation as a multifaceted virulence and defensive mechanism, enabling the bacterium to thrive in harsh conditions. This review discusses the molecular mechanisms contributing to biofilm formation across its developmental stages, hence representing a step forward in developing promising strategies for impeding or eradicating biofilms. During staphylococcal biofilm development, cell wall-anchored proteins attach bacterial cells to biotic or abiotic surfaces; extracellular polymeric substances build scaffolds for biofilm formation; the cidABC operon controls cell lysis within the biofilm, and proteases facilitate dispersal. Beside the three main sequential stages of biofilm formation (attachment, maturation, and dispersal), this review unveils two unique developmental stages in the biofilm formation process for MRSA; multiplication and exodus. We also highlighted the quorum sensing as a cell-to-cell communication process, allowing distant bacterial cells to adapt to the conditions surrounding the bacterial biofilm. In S. aureus, the quorum sensing process is mediated by autoinducing peptides (AIPs) as signaling molecules, with the accessory gene regulator system playing a pivotal role in orchestrating the production of AIPs and various virulence factors. Several quorum inhibitors showed promising anti-virulence and antibiofilm effects that vary in type and function according to the targeted molecule. Disrupting the biofilm architecture and eradicating sessile bacterial cells are crucial steps to prevent colonization on other surfaces or organs. In this context, nanoparticles emerge as efficient carriers for delivering antimicrobial and antibiofilm agents throughout the biofilm architecture. Although metal-based nanoparticles have been previously used in combatting biofilms, its non-degradability and toxicity within the human body presents a real challenge. Therefore, organic nanoparticles in conjunction with quorum inhibitors have been proposed as a promising strategy against biofilms. As nanotherapeutics continue to gain recognition as an antibiofilm strategy, the development of more antibiofilm nanotherapeutics could offer a promising solution to combat biofilm-mediated resistance.
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Affiliation(s)
- Nirmeen Aboelnaga
- Center for Genomics, Helmy Institute for Medical Sciences, Zewail City of Science and Technology, Giza, Egypt
- Biomedical Sciences Program, University of Science and Technology, Zewail City of Science and Technology, Giza, Egypt
| | - Salma W Elsayed
- Center for Genomics, Helmy Institute for Medical Sciences, Zewail City of Science and Technology, Giza, Egypt
- Biomedical Sciences Program, University of Science and Technology, Zewail City of Science and Technology, Giza, Egypt
- Department of Microbiology & Immunology, Faculty of Pharmacy, Ain Shams University, Cairo, Egypt
| | - Nehal Adel Abdelsalam
- Center for Genomics, Helmy Institute for Medical Sciences, Zewail City of Science and Technology, Giza, Egypt
- Biomedical Sciences Program, University of Science and Technology, Zewail City of Science and Technology, Giza, Egypt
- Department of Microbiology and Immunology, Faculty of Pharmacy, Cairo University, Cairo, Egypt
| | - Salma Salem
- Center for Genomics, Helmy Institute for Medical Sciences, Zewail City of Science and Technology, Giza, Egypt
- Biomedical Sciences Program, University of Science and Technology, Zewail City of Science and Technology, Giza, Egypt
| | - Nehal A Saif
- Center for Genomics, Helmy Institute for Medical Sciences, Zewail City of Science and Technology, Giza, Egypt
- Biomedical Sciences Program, University of Science and Technology, Zewail City of Science and Technology, Giza, Egypt
| | - Manar Elsayed
- Center for Genomics, Helmy Institute for Medical Sciences, Zewail City of Science and Technology, Giza, Egypt
- Biomedical Sciences Program, University of Science and Technology, Zewail City of Science and Technology, Giza, Egypt
| | - Shehab Ayman
- Center for Genomics, Helmy Institute for Medical Sciences, Zewail City of Science and Technology, Giza, Egypt
- Biomedical Sciences Program, University of Science and Technology, Zewail City of Science and Technology, Giza, Egypt
| | - Maha Nasr
- Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, Ain Shams University, Cairo, Egypt
| | - Mohamed Elhadidy
- Center for Genomics, Helmy Institute for Medical Sciences, Zewail City of Science and Technology, Giza, Egypt.
- Biomedical Sciences Program, University of Science and Technology, Zewail City of Science and Technology, Giza, Egypt.
- Department of Bacteriology, Mycology and Immunology, Faculty of Veterinary Medicine, Mansoura University, Mansoura, Egypt.
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Trottier MC, de Oliveira Pereira T, Groleau MC, Hoffman LR, Dandekar AA, Déziel E. The end of the reign of a "master regulator''? A defect in function of the LasR quorum sensing regulator is a common feature of Pseudomonas aeruginosa isolates. mBio 2024; 15:e0237623. [PMID: 38315035 PMCID: PMC10936206 DOI: 10.1128/mbio.02376-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2024] Open
Abstract
Pseudomonas aeruginosa, a bacterium causing infections in immunocompromised individuals, regulates several of its virulence functions using three interlinked quorum sensing (QS) systems (las, rhl, and pqs). Despite its presumed importance in regulating virulence, dysfunction of the las system regulator LasR occurs frequently in strains isolated from various environments, including clinical infections. This newfound abundance of LasR-defective strains calls into question existing hypotheses regarding their selection. Indeed, current assumptions concerning factors driving the emergence of LasR-deficient isolates and the role of LasR in the QS hierarchy must be reconsidered. Here, we propose that LasR is not the primary master regulator of QS in all P. aeruginosa genetic backgrounds, even though it remains ecologically significant. We also revisit and complement current knowledge on the ecology of LasR-dependent QS in P. aeruginosa, discuss the hypotheses explaining the putative adaptive benefits of selecting against LasR function, and consider the implications of this renewed understanding.
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Affiliation(s)
- Mylène C. Trottier
- Centre Armand-Frappier Santé Biotechnologie, Institut National de la Recherche Scientifique (INRS), Laval, Québec, Canada
| | - Thays de Oliveira Pereira
- Centre Armand-Frappier Santé Biotechnologie, Institut National de la Recherche Scientifique (INRS), Laval, Québec, Canada
| | - Marie-Christine Groleau
- Centre Armand-Frappier Santé Biotechnologie, Institut National de la Recherche Scientifique (INRS), Laval, Québec, Canada
| | - Lucas R. Hoffman
- Departments of Pediatrics and Microbiology, University of Washington, Seattle, Washington, USA
| | - Ajai A. Dandekar
- Departments of Medicine and Microbiology, University of Washington, Seattle, Washington, USA
| | - Eric Déziel
- Centre Armand-Frappier Santé Biotechnologie, Institut National de la Recherche Scientifique (INRS), Laval, Québec, Canada
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Zhang J, Ma Q, Wang C, Meng N. Unraveling the signaling roles of indole in an opportunistic pathogen Pseudomonas aeruginosa strain Jade-X. Chemosphere 2024; 352:141482. [PMID: 38387666 DOI: 10.1016/j.chemosphere.2024.141482] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 12/29/2023] [Accepted: 02/15/2024] [Indexed: 02/24/2024]
Abstract
Pseudomonas aeruginosa, which can produce several toxins and form biofilm, is listed among the priority pathogens. Indole is a ubiquitous aromatic pollutant and signaling molecule produced by tryptophanase in bacteria. Herein, the impacts of indole on a newly isolated P. aeruginosa strain Jade-X were systematically investigated. Indole (0.5-2.0 mM) enhanced the biofilm production by 1.33-2.31-fold after 24 h incubation at 30 °C. However, the effects indole on biofilm formation were intricate and closely intertwined with factors such as incubation temperature, bacterial growth stage, and indole concentration. The twitching motility was enhanced by 1.15-1.99-fold by indole, potentially facilitating surface exploration and biofilm development. Indole reduced the production of virulence factors (pyocyanin and pyoverdine) as well as altered the surface properties (zeta potential and hydrophobicity). Transcriptional analysis revealed that indole (1.0 mM) significantly downregulated mexGHI-opmD efflux genes (4.73-6.91-fold) and virulence-related genes (pqs, pch, and pvd clusters, and flagella-related genes), while upregulating pili-related genes in strain Jade-X. The quorum sensing related signal regulators, including RhlR, LasR, and MvfR (PqsR), were not altered by indole, while other six transcriptional regulators (AmrZ, BfmR, PchR, QscR, SoxR, and SphR) were significantly affected, implying that indole effects might be regulated in a complex and delicate manner. This study should provide new insights into our understanding of indole signaling roles.
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Affiliation(s)
- Jiaxin Zhang
- Institute of Environmental Systems Biology, College of Environmental Science and Engineering, Dalian Maritime University, Dalian, 116026, China
| | - Qiao Ma
- Institute of Environmental Systems Biology, College of Environmental Science and Engineering, Dalian Maritime University, Dalian, 116026, China.
| | - Caihong Wang
- Institute of Environmental Systems Biology, College of Environmental Science and Engineering, Dalian Maritime University, Dalian, 116026, China
| | - Nan Meng
- Institute of Environmental Systems Biology, College of Environmental Science and Engineering, Dalian Maritime University, Dalian, 116026, China
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15
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Zhou Q, Mi K, Ma W, Feng F, Huo M, Sun Y, Huang L. Metagenomic analysis reveals impact of acyl homoserine endolipid-like signaling molecules on the aqueous sediment resistome under florfenicol stress. Bioresour Technol 2024; 395:130318. [PMID: 38219924 DOI: 10.1016/j.biortech.2024.130318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Revised: 01/09/2024] [Accepted: 01/10/2024] [Indexed: 01/16/2024]
Abstract
Quorum sensing potentially helps microorganisms adapt to antibiotic stress encountered in the environment. This experiment investigated the effect of acyl homoserine endolipid-like signaling molecules on microbial antibiotic resistance gene structures in aqueous sediments under florfenicol stress. Additional acyl homoserine endolipid-like signaling molecules (AHLs) alter the structure of multidrug resistance genes in florfenicol-stressed sediments, particularly the multidrug resistance efflux pump gene family. Prophages and integrative and conjugative elements (ICEs) determined the resistance genes structure, and pathways related to mobile genetic elements (MGEs) transfer may play an essential role in this process. The practical application of AHLs to regulate quorum sensing systems may alter bacterial stress responses to environmental florfenicol residues, thereby reducing the development of antibiotic resistance in the environment.
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Affiliation(s)
- Qin Zhou
- National Reference Laboratory of Veterinary Drug Residues, Huazhong Agricultural University, Wuhan 430070, China; MOA Key Laboratory for Detection of Veterinary Drug Residues, Wuhan 430070, China; MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products,Whan 430070, China; Frontiers Science Center for Animal Breeding and Sustainable Production, Wuhan 430070, China; National Laboratory of Safety Evaluation (Environmental Assessment) of Veterinary Drugs, National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, College of Veterinary Medicine, South China Agricultural University, 483 Wushan Road, Guangzhou 510642, China|
| | - Kun Mi
- National Reference Laboratory of Veterinary Drug Residues, Huazhong Agricultural University, Wuhan 430070, China; MOA Key Laboratory for Detection of Veterinary Drug Residues, Wuhan 430070, China
| | - Wenjin Ma
- National Reference Laboratory of Veterinary Drug Residues, Huazhong Agricultural University, Wuhan 430070, China; MOA Key Laboratory for Detection of Veterinary Drug Residues, Wuhan 430070, China; Frontiers Science Center for Animal Breeding and Sustainable Production, Wuhan 430070, China
| | - Fenglin Feng
- National Laboratory of Safety Evaluation (Environmental Assessment) of Veterinary Drugs, National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, College of Veterinary Medicine, South China Agricultural University, 483 Wushan Road, Guangzhou 510642, China|
| | - Meixia Huo
- National Reference Laboratory of Veterinary Drug Residues, Huazhong Agricultural University, Wuhan 430070, China; MOA Key Laboratory for Detection of Veterinary Drug Residues, Wuhan 430070, China; Frontiers Science Center for Animal Breeding and Sustainable Production, Wuhan 430070, China
| | - Yongxue Sun
- National Laboratory of Safety Evaluation (Environmental Assessment) of Veterinary Drugs, National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, College of Veterinary Medicine, South China Agricultural University, 483 Wushan Road, Guangzhou 510642, China|
| | - Lingli Huang
- National Reference Laboratory of Veterinary Drug Residues, Huazhong Agricultural University, Wuhan 430070, China; MOA Key Laboratory for Detection of Veterinary Drug Residues, Wuhan 430070, China; MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products,Whan 430070, China; Frontiers Science Center for Animal Breeding and Sustainable Production, Wuhan 430070, China.
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Kameswaran S, Gujjala S, Zhang S, Kondeti S, Mahalingam S, Bangeppagari M, Bellemkonda R. Quenching and quorum sensing in bacterial bio-films. Res Microbiol 2024; 175:104085. [PMID: 37268165 DOI: 10.1016/j.resmic.2023.104085] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 05/24/2023] [Accepted: 05/25/2023] [Indexed: 06/04/2023]
Abstract
Quorum sensing (QS) is the ability of bacteria to monitor their population density and adjust gene expression accordingly. QS-regulated processes include host-microbe interactions, horizontal gene transfer, and multicellular behaviours (such as the growth and development of biofilm). The creation, transfer, and perception of bacterial chemicals known as autoinducers or QS signals are necessary for QS signalling (e.g. N-acylhomoserine lactones). Quorum quenching (QQ), another name for the disruption of QS signalling, comprises a wide range of events and mechanisms that are described and analysed in this study. In order to better comprehend the targets of the QQ phenomena that organisms have naturally developed and are currently being actively researched from practical perspectives, we first surveyed the diversity of QS-signals and QS-associated responses. Next, the mechanisms, molecular players, and targets related to QS interference are discussed, with a focus on natural QQ enzymes and compounds that function as QS inhibitors. To illustrate the processes and biological functions of QS inhibition in microbe-microbe and host-microbe interactions, a few QQ paradigms are described in detail. Finally, certain QQ techniques are offered as potential instruments in a variety of industries, including agriculture, medical, aquaculture, crop production, and anti-biofouling areas.
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Affiliation(s)
- Srinivasan Kameswaran
- Department of Botany, Vikrama Simhapuri University College, Kavali, Andhra Pradesh, India
| | - Sudhakara Gujjala
- Department of Biochemistry, Sri Krishnadevaray a University, Ananthapuram, Andhra Pradesh, India
| | - Shaoqing Zhang
- School of Chemistry and Civil Engineering, Shaoguan University, Shaoguan, 512005, PR China
| | - Suresh Kondeti
- Multi-Disciplinary Research Unit, Nizam's Institute of Medical Sciences, Hyderabad, 500082, India
| | - Sundararajan Mahalingam
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE, USA
| | - Manjunatha Bangeppagari
- Department of Cell Biology & Molecular Genetics, Sri Devaraj Urs Academy of Higher Education and Research (Deemed to Be University), Tamaka, Kolar, 563103, Karnataka, India
| | - Ramesh Bellemkonda
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE, USA.
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Cai Y, Zhang X. The atypical organization of the luxI/R family genes in AHL-driven quorum-sensing circuits. J Bacteriol 2024; 206:e0043023. [PMID: 38240569 PMCID: PMC10882985 DOI: 10.1128/jb.00430-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2024] Open
Abstract
Quorum sensing (QS) is an elaborate regulatory mechanism associated with virulence and bacterial adaptation to the changing environment. QS is widespread in Proteobacteria and acts primarily through N-acylhomoserine lactone (AHL) signals. At the core of the AHL-driven QS systems are the AHL synthase gene (luxI family) and its cognate transcriptional regulator gene (luxR family). Several QS systems display one or more genes intervening between the luxI and luxR, in which gene arrangements are notably different due to the relative position and the transcriptional orientation between the essential luxI/R and the genes of location correlation. These adjacent genes may exert a regulatory impact on the primary QS genes or contribute toward an extension of QS regulatory control. In this review, we describe the organization of AHL-driven QS genes based on previous research and specific genome databases and provide new insights into these atypical QS gene arrangements.
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Affiliation(s)
- Yuyuan Cai
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Xuehong Zhang
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
- National Experimental Teaching Center for Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
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Rostamnejad D, Esnaashari F, Zahmatkesh H, Rasti B, Zamani H. Diclofenac-loaded PLGA nanoparticles downregulate LasI/R quorum sensing genes in pathogenic P. aeruginosa isolates. Arch Microbiol 2024; 206:112. [PMID: 38374471 DOI: 10.1007/s00203-023-03809-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Revised: 12/18/2023] [Accepted: 12/19/2023] [Indexed: 02/21/2024]
Abstract
Poly(lactic-co-glycolic acid) (PLGA) is a biocompatible polymer that can gradually and consistently release drugs in a controlled manner. In this study, diclofenac sodium-loaded PLGA nanoparticles (DS-PLGA NPs) were produced by solvent evaporation technique and characterized using SEM, DLS, and zeta potential analyses. The antibacterial and antivirulence potential of DS-PLGA NPs against P. aeruginosa strains were examined using broth microdilution, crystal violet staining, hemolysis, and twitching quantification assays. Furthermore, the expression of the quorum sensing (QS) genes, lasI and lasR in P. aeruginosa strains after treatment with 1/2 MIC of DS-PLGA NPs was assessed using real-time PCR. SEM imaging of the synthesized NPs exhibited that the NPs have a spherical structure with a size range of 60-150 nm. The zeta potential of the NPs was - 15.2 mV, while the size of the particles in the aquatic environment was in a range of 111.5-153.8 nm. The MIC of prepared NPs against various strains of P. aeruginosa ranged from 4.5 to 9 mg/mL. Moreover, exposure of bacteria to sub-MIC of DS-PLGA NPs significantly down-regulated the expression of the lasI and lasR genes to 0.51- and 0.75-fold, respectively. Further, prepared NPs efficiently reduced the biofilm formation of P. aeruginosa strains by 9-27%, compared with the controls. Besides, DS-PLGA NPs showed considerable attenuation in bacterial hemolytic activity by 32-88% and twitching motility by 0-32.3%, compared with untreated cells. Overall, the present work exhibited the anti-QS activity of DS-PLGA NPs, which could be a safe and useful approach for treating P. aeruginosa infections.
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Affiliation(s)
- Dorna Rostamnejad
- Department of Microbiology, Faculty of Basic Sciences, Lahijan Branch, Islamic Azad University (IAU), Lahijan, Guilan, Iran
| | - Fatemeh Esnaashari
- Department of Biology, Faculty of Basic Sciences, Lahijan Branch, Islamic Azad University (IAU), Lahijan, Guilan, Iran
| | - Hossein Zahmatkesh
- Department of Microbiology, Faculty of Basic Sciences, Lahijan Branch, Islamic Azad University (IAU), Lahijan, Guilan, Iran
| | - Behnam Rasti
- Department of Microbiology, Faculty of Basic Sciences, Lahijan Branch, Islamic Azad University (IAU), Lahijan, Guilan, Iran.
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19
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Zeng M, Sarker B, Rondthaler SN, Vu V, Andrews LB. Identifying LasR Quorum Sensors with Improved Signal Specificity by Mapping the Sequence-Function Landscape. ACS Synth Biol 2024; 13:568-589. [PMID: 38206199 DOI: 10.1021/acssynbio.3c00543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2024]
Abstract
Programmable intercellular signaling using components of naturally occurring quorum sensing can allow for coordinated functions to be engineered in microbial consortia. LuxR-type transcriptional regulators are widely used for this purpose and are activated by homoserine lactone (HSL) signals. However, they often suffer from imperfect molecular discrimination of structurally similar HSLs, causing misregulation within engineered consortia containing multiple HSL signals. Here, we studied one such example, the regulator LasR from Pseudomonas aeruginosa. We elucidated its sequence-function relationship for ligand specificity using targeted protein engineering and multiplexed high-throughput biosensor screening. A pooled combinatorial saturation mutagenesis library (9,486 LasR DNA sequences) was created by mutating six residues in LasR's β5 sheet with single, double, or triple amino acid substitutions. Sort-seq assays were performed in parallel using cognate and noncognate HSLs to quantify each corresponding sensor's response to each HSL signal, which identified hundreds of highly specific variants. Sensor variants identified were individually assayed and exhibited up to 60.6-fold (p = 0.0013) improved relative activation by the cognate signal compared to the wildtype. Interestingly, we uncovered prevalent mutational epistasis and previously unidentified residues contributing to signal specificity. The resulting sensors with negligible signal crosstalk could be broadly applied to engineer bacteria consortia.
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Affiliation(s)
- Min Zeng
- Department of Chemical Engineering, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
| | - Biprodev Sarker
- Department of Chemical Engineering, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
| | - Stephen N Rondthaler
- Department of Chemical Engineering, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
| | - Vanessa Vu
- Department of Biochemistry and Molecular Biology, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
| | - Lauren B Andrews
- Department of Chemical Engineering, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
- Molecular and Cellular Biology Graduate Program, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
- Biotechnology Training Program, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
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20
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Mould DL, Finger CE, Conaway A, Botelho N, Stuut SE, Hogan DA. Citrate cross-feeding by Pseudomonas aeruginosa supports lasR mutant fitness. mBio 2024; 15:e0127823. [PMID: 38259061 PMCID: PMC10865840 DOI: 10.1128/mbio.01278-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Accepted: 12/11/2023] [Indexed: 01/24/2024] Open
Abstract
Cross-feeding of metabolites between subpopulations can affect cell phenotypes and population-level behaviors. In chronic Pseudomonas aeruginosa lung infections, subpopulations with loss-of-function (LOF) mutations in the lasR gene are common. LasR, a transcription factor often described for its role in virulence factor expression, also impacts metabolism, which, in turn, affects interactions between LasR+ and LasR- genotypes. Prior transcriptomic analyses suggested that citrate, a metabolite secreted by many cell types, induces virulence factor production when both genotypes are together. An unbiased analysis of the intracellular metabolome revealed broad differences including higher levels of citrate in lasR LOF mutants. Citrate consumption by LasR- strains required the CbrAB two-component system, which relieves carbon catabolite repression and is elevated in lasR LOF mutants. Within mixed communities, the citrate-responsive two-component system TctED and its gene targets OpdH (porin) and TctABC (citrate transporter) that are predicted to be under catabolite repression control were induced and required for enhanced RhlR/I-dependent signaling, pyocyanin production, and fitness of LasR- strains. Citrate uptake by LasR- strains markedly increased pyocyanin production in co-culture with Staphylococcus aureus, which also secretes citrate and frequently co-infects with P. aeruginosa. This citrate-induced restoration of virulence factor production by LasR- strains in communities with diverse species or genotypes may offer an explanation for the contrast observed between the markedly deficient virulence factor production of LasR- strains in monocultures and their association with the most severe forms of cystic fibrosis lung infections. These studies highlight the impact of secreted metabolites in mixed microbial communities.IMPORTANCECross-feeding of metabolites can change community composition, structure, and function. Here, we unravel a cross-feeding mechanism between frequently co-observed isolate genotypes in chronic Pseudomonas aeruginosa lung infections. We illustrate an example of how clonally derived diversity in a microbial communication system enables intra- and inter-species cross-feeding. Citrate, a metabolite released by many cells including P. aeruginosa and Staphylococcus aureus, was differentially consumed between genotypes. Since these two pathogens frequently co-occur in the most severe cystic fibrosis lung infections, the cross-feeding-induced virulence factor expression and fitness described here between diverse genotypes exemplify how co-occurrence can facilitate the development of worse disease outcomes.
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Affiliation(s)
- Dallas L. Mould
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
| | - Carson E. Finger
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
| | - Amy Conaway
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
| | - Nico Botelho
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
| | - Stacie E. Stuut
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
| | - Deborah A. Hogan
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
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21
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Kristensen R, Andersen JB, Rybtke M, Jansen CU, Fritz BG, Kiilerich RO, Uhd J, Bjarnsholt T, Qvortrup K, Tolker-Nielsen T, Givskov M, Jakobsen TH. Inhibition of Pseudomonas aeruginosa quorum sensing by chemical induction of the MexEF-oprN efflux pump. Antimicrob Agents Chemother 2024; 68:e0138723. [PMID: 38189278 PMCID: PMC10848761 DOI: 10.1128/aac.01387-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Accepted: 11/17/2023] [Indexed: 01/09/2024] Open
Abstract
The cell-to-cell communication system quorum sensing (QS), used by various pathogenic bacteria to synchronize gene expression and increase host invasion potentials, is studied as a potential target for persistent infection control. To search for novel molecules targeting the QS system in the Gram-negative opportunistic pathogen Pseudomonas aeruginosa, a chemical library consisting of 3,280 small compounds from LifeArc was screened. A series of 10 conjugated phenones that have not previously been reported to target bacteria were identified as inhibitors of QS in P. aeruginosa. Two lead compounds (ethylthio enynone and propylthio enynone) were re-synthesized for verification of activity and further elucidation of the mode of action. The isomeric pure Z-ethylthio enynone was used for RNA sequencing, revealing a strong inhibitor of QS-regulated genes, and the QS-regulated virulence factors rhamnolipid and pyocyanin were significantly decreased by treatment with the compounds. A transposon mutagenesis screen performed in a newly constructed lasB-gfp monitor strain identified the target of Z-ethylthio enynone in P. aeruginosa to be the MexEF-OprN efflux pump, which was further established using defined mex knockout mutants. Our data indicate that the QS inhibitory capabilities of Z-ethylthio enynone were caused by the drainage of intracellular signal molecules as a response to chemical-induced stimulation of the MexEF-oprN efflux pump, thereby inhibiting the autogenerated positive feedback and its enhanced signal-molecule synthesis.
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Affiliation(s)
- Rasmus Kristensen
- Department of Immunology and Microbiology, Costerton Biofilm Center, University of Copenhagen, Copenhagen, Denmark
| | - Jens Bo Andersen
- Department of Immunology and Microbiology, Costerton Biofilm Center, University of Copenhagen, Copenhagen, Denmark
| | - Morten Rybtke
- Department of Immunology and Microbiology, Costerton Biofilm Center, University of Copenhagen, Copenhagen, Denmark
| | | | - Blaine Gabriel Fritz
- Department of Immunology and Microbiology, Costerton Biofilm Center, University of Copenhagen, Copenhagen, Denmark
| | - Rikke Overgaard Kiilerich
- Department of Immunology and Microbiology, Costerton Biofilm Center, University of Copenhagen, Copenhagen, Denmark
| | - Jesper Uhd
- Department of Chemistry, Technical University of Denmark, Lyngby, Denmark
| | - Thomas Bjarnsholt
- Department of Immunology and Microbiology, Costerton Biofilm Center, University of Copenhagen, Copenhagen, Denmark
- Department of Clinical Microbiology, Rigshospitalet, Copenhagen, Denmark
| | - Katrine Qvortrup
- Department of Chemistry, Technical University of Denmark, Lyngby, Denmark
| | - Tim Tolker-Nielsen
- Department of Immunology and Microbiology, Costerton Biofilm Center, University of Copenhagen, Copenhagen, Denmark
| | - Michael Givskov
- Department of Immunology and Microbiology, Costerton Biofilm Center, University of Copenhagen, Copenhagen, Denmark
| | - Tim Holm Jakobsen
- Department of Immunology and Microbiology, Costerton Biofilm Center, University of Copenhagen, Copenhagen, Denmark
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22
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Muriel-Millán LF, Montelongo-Martínez LF, González-Valdez A, Bedoya-Pérez LP, Cocotl-Yañez M, Soberón-Chávez G. The alternative sigma factor RpoS regulates Pseudomonas aeruginosa quorum sensing response by repressing the pqsABCDE operon and activating vfr. Mol Microbiol 2024; 121:291-303. [PMID: 38169053 DOI: 10.1111/mmi.15224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Revised: 12/02/2023] [Accepted: 12/22/2023] [Indexed: 01/05/2024]
Abstract
Pseudomonas aeruginosa is an important opportunistic pathogen. Several of its virulence-related processes, including the synthesis of pyocyanin (PYO) and biofilm formation, are controlled by quorum sensing (QS). It has been shown that the alternative sigma factor RpoS regulates QS through the reduction of lasR and rhlR transcription (encoding QS regulators). However, paradoxically, the absence of RpoS increases PYO production and biofilm development (that are RhlR dependent) by unknown mechanisms. Here, we show that RpoS represses pqsE transcription, which impacts the stability and activity of RhlR. In the absence of RpoS, rhlR transcript levels are reduced but not the RhlR protein concentration, presumably by its stabilization by PqsE, whose expression is increased. We also report that PYO synthesis and the expression of pqsE and phzA1B1C1D1E1F1G1 operon exhibit the same pattern at different RpoS concentrations, suggesting that the RpoS-dependent PYO production is due to its ability to modify PqsE concentration, which in turn modulates the activation of the phzA1 promoter by RhlR. Finally, we demonstrate that RpoS favors the expression of Vfr, which activates the transcription of lasR and rhlR. Our study contributes to the understanding of how RpoS modulates the QS response in P. aeruginosa, exerting both negative and positive regulation.
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Affiliation(s)
- Luis Felipe Muriel-Millán
- Departamento de Biología Molecular y Biotecnología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad Universitaria, Ciudad de México, Mexico
| | - Luis Fernando Montelongo-Martínez
- Departamento de Biología Molecular y Biotecnología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad Universitaria, Ciudad de México, Mexico
| | - Abigail González-Valdez
- Departamento de Biología Molecular y Biotecnología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad Universitaria, Ciudad de México, Mexico
| | - Leidy Patricia Bedoya-Pérez
- Programa de Biología Sintética, Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, Mexico
| | - Miguel Cocotl-Yañez
- Departamento de Microbiología y Parasitología, Facultad de Medicina, Universidad Nacional Autónoma de México, Ciudad Universitaria, Ciudad de México, Mexico
| | - Gloria Soberón-Chávez
- Departamento de Biología Molecular y Biotecnología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad Universitaria, Ciudad de México, Mexico
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23
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Liu XY, Li CM, Lyu CX, Li ZQ, Huang YH. [Research progress of traditional Chinese medicines as quorum sensing inhibitors in collaboration with antibiotics to inhibit drug-resistant bacteria]. Zhongguo Zhong Yao Za Zhi 2024; 49:653-660. [PMID: 38621869 DOI: 10.19540/j.cnki.cjcmm.20231127.601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/17/2024]
Abstract
Quorum sensing system regulates the expression of genes related to bacterial growth, metabolism and other behaviors by sensing bacterial density, and controls the unified action of the entire bacterial population. This mechanism can ensure the normal secretion of bacterial metabolites and the stability of the biofilm microenvironment, providing protection for the formation of biofilms and the normal growth and reproduction of bacteria. Traditional Chinese medicine, capable of quorum sensing inhibition, can inhibit the formation of bacterial biofilms, reduce bacterial resistance, and enhance the anti-infection ability of antibiotics when combined with antibiotics. In recent years, the combination of traditional Chinese and Western medicine in the treatment of drug-resistant bacterial infections has become a research hotspot. Starting with the associations between quorum sensing, biofilm and drug-resistant bacteria, this paper reviews the relevant studies about the combined application of traditional Chinese medicines as quorum sensing inhibitors with antibiotics in the treatment of drug-resistant bacteria. This review is expected to provide ideas for the development of new clinical treatment methods and novel anti-infection drugs.
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Affiliation(s)
- Xin-Yue Liu
- Tianjin University of Traditional Chinese Medicine Tianjin 301617, China the Second Affiliated Hospital of Tianjin University of Traditional Chinese Medicine Tianjin 300250, China
| | - Chen-Ming Li
- Tianjin University of Traditional Chinese Medicine Tianjin 301617, China the Second Affiliated Hospital of Tianjin University of Traditional Chinese Medicine Tianjin 300250, China
| | - Chun-Xiao Lyu
- the Second Affiliated Hospital of Tianjin University of Traditional Chinese Medicine Tianjin 300250, China
| | - Zi-Qiang Li
- the Second Affiliated Hospital of Tianjin University of Traditional Chinese Medicine Tianjin 300250, China
| | - Yu-Hong Huang
- the Second Affiliated Hospital of Tianjin University of Traditional Chinese Medicine Tianjin 300250, China
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24
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Vinayavekhin N, Wattanophas T, Murphy MF, Vangnai AS, Hobbs G. Metabolomics responses and tolerance of Pseudomonas aeruginosa under acoustic vibration stress. PLoS One 2024; 19:e0297030. [PMID: 38285708 PMCID: PMC10824448 DOI: 10.1371/journal.pone.0297030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Accepted: 12/25/2023] [Indexed: 01/31/2024] Open
Abstract
Sound has been shown to impact microbial behaviors. However, our understanding of the chemical and molecular mechanisms underlying these microbial responses to acoustic vibration is limited. In this study, we used untargeted metabolomics analysis to investigate the effects of 100-Hz acoustic vibration on the intra- and extracellular hydrophobic metabolites of P. aeruginosa PAO1. Our findings revealed increased levels of fatty acids and their derivatives, quinolones, and N-acylethanolamines upon sound exposure, while rhamnolipids (RLs) showed decreased levels. Further quantitative real-time polymerase chain reaction experiments showed slight downregulation of the rhlA gene (1.3-fold) and upregulation of fabY (1.5-fold), fadE (1.7-fold), and pqsA (1.4-fold) genes, which are associated with RL, fatty acid, and quinolone biosynthesis. However, no alterations in the genes related to the rpoS regulators or quorum-sensing networks were observed. Supplementing sodium oleate to P. aeruginosa cultures to simulate the effects of sound resulted in increased tolerance of P. aeruginosa in the presence of sound at 48 h, suggesting a potential novel response-tolerance correlation. In contrast, adding RL, which went against the response direction, did not affect its growth. Overall, these findings provide potential implications for the control and manipulation of virulence and bacterial characteristics for medical and industrial applications.
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Affiliation(s)
- Nawaporn Vinayavekhin
- Center of Excellence in Natural Products Chemistry, Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok, Thailand
- Center of Excellence in Biocatalyst and Sustainable Biotechnology, Faculty of Science, Chulalongkorn University, Bangkok, Thailand
| | - Thanyaporn Wattanophas
- Center of Excellence in Natural Products Chemistry, Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok, Thailand
| | - Mark Francis Murphy
- School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Liverpool, United Kingdom
| | - Alisa S. Vangnai
- Center of Excellence in Biocatalyst and Sustainable Biotechnology, Faculty of Science, Chulalongkorn University, Bangkok, Thailand
- Department of Biochemistry, Faculty of Science, Chulalongkorn University, Bangkok, Thailand
| | - Glyn Hobbs
- School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Liverpool, United Kingdom
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25
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Zeng M, Sarker B, Howitz N, Shah I, Andrews LB. Synthetic Homoserine Lactone Sensors for Gram-Positive Bacillus subtilis Using LuxR-Type Regulators. ACS Synth Biol 2024; 13:282-299. [PMID: 38079538 PMCID: PMC10805106 DOI: 10.1021/acssynbio.3c00504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Revised: 10/11/2023] [Accepted: 10/18/2023] [Indexed: 01/23/2024]
Abstract
A universal biochemical signal for bacterial cell-cell communication could facilitate programming dynamic responses in diverse bacterial consortia. However, the classical quorum sensing paradigm is that Gram-negative and Gram-positive bacteria generally communicate via homoserine lactones (HSLs) or oligopeptide molecular signals, respectively, to elicit population responses. Here, we create synthetic HSL sensors for Gram-positive Bacillus subtilis 168 using allosteric LuxR-type regulators (RpaR, LuxR, RhlR, and CinR) and synthetic promoters. Promoters were combinatorially designed from different sequence elements (-35, -16, -10, and transcriptional start regions). We quantified the effects of these combinatorial promoters on sensor activity and determined how regulator expression affects its activation, achieving up to 293-fold activation. Using the statistical design of experiments, we identified significant effects of promoter regions and pairwise interactions on sensor activity, which helped to understand the sequence-function relationships for synthetic promoter design. We present the first known set of functional HSL sensors (≥20-fold dynamic range) in B. subtilis for four different HSL chemical signals: p-coumaroyl-HSL, 3-oxohexanoyl-HSL, n-butyryl-HSL, and n-(3-hydroxytetradecanoyl)-HSL. This set of synthetic HSL sensors for a Gram-positive bacterium can pave the way for designable interspecies communication within microbial consortia.
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Affiliation(s)
- Min Zeng
- Department
of Chemical Engineering, University of Massachusetts
Amherst, Amherst, Massachusetts 01003, United States
| | - Biprodev Sarker
- Department
of Chemical Engineering, University of Massachusetts
Amherst, Amherst, Massachusetts 01003, United States
| | - Nathaniel Howitz
- Department
of Chemical Engineering, University of Massachusetts
Amherst, Amherst, Massachusetts 01003, United States
| | - Ishita Shah
- Department
of Chemical Engineering, University of Massachusetts
Amherst, Amherst, Massachusetts 01003, United States
| | - Lauren B. Andrews
- Department
of Chemical Engineering, University of Massachusetts
Amherst, Amherst, Massachusetts 01003, United States
- Molecular
and Cellular Biology Graduate Program, University
of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
- Biotechnology
Training Program, University of Massachusetts
Amherst, Amherst, Massachusetts 01003, United States
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26
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Martins PMM, Granato LM, Morgan T, Nalin JL, Takita MA, Alfenas-Zerbini P, de Souza AA. Analysis of CRISPR-Cas loci distribution in Xanthomonas citri and its possible control by the quorum sensing system. FEMS Microbiol Lett 2024; 371:fnae005. [PMID: 38244227 DOI: 10.1093/femsle/fnae005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 10/04/2023] [Accepted: 01/18/2024] [Indexed: 01/22/2024] Open
Abstract
Xanthomonas is an important genus of plant-associated bacteria that causes significant yield losses of economically important crops worldwide. Different approaches have assessed genetic diversity and evolutionary interrelationships among the Xanthomonas species. However, information from clustered regularly interspaced short palindromic repeats (CRISPRs) has yet to be explored. In this work, we analyzed the architecture of CRISPR-Cas loci and presented a sequence similarity-based clustering of conserved Cas proteins in different species of Xanthomonas. Although absent in many investigated genomes, Xanthomonas harbors subtype I-C and I-F CRISPR-Cas systems. The most represented species, Xanthomonas citri, presents a great diversity of genome sequences with an uneven distribution of the CRISPR-Cas systems among the subspecies/pathovars. Only X. citri subsp. citri and X. citri pv. punicae have these systems, exclusively of subtype I-C system. Moreover, the most likely targets of the X. citri CRISPR spacers are viruses (phages). At the same time, few are plasmids, indicating that CRISPR/Cas system is possibly a mechanism to control the invasion of foreign DNA. We also showed in X. citri susbp. citri that the cas genes are regulated by the diffusible signal factor, the quorum sensing (QS) signal molecule, according to cell density increases, and under environmental stress like starvation. These results suggest that the regulation of CRISPR-Cas by QS occurs to activate the gene expression only during phage infection or due to environmental stresses, avoiding a possible reduction in fitness. Although more studies are needed, CRISPR-Cas systems may have been selected in the Xanthomonas genus throughout evolution, according to the cost-benefit of protecting against biological threats and fitness maintenance in challenging conditions.
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Affiliation(s)
| | - Laís Moreira Granato
- Citrus Research Center "Sylvio Moreira", Agronomic Institute (IAC), Cordeiropolis-SP 13490-970, Brazil
| | - Túlio Morgan
- Department of Microbiology, Institute of Biotechnology Applied to Agriculture (BIOAGRO), Federal University of Viçosa, Viçosa-MG 36570-900, Brazil
| | - Julia Lopes Nalin
- Citrus Research Center "Sylvio Moreira", Agronomic Institute (IAC), Cordeiropolis-SP 13490-970, Brazil
| | - Marco Aurélio Takita
- Citrus Research Center "Sylvio Moreira", Agronomic Institute (IAC), Cordeiropolis-SP 13490-970, Brazil
| | - Poliane Alfenas-Zerbini
- Department of Microbiology, Institute of Biotechnology Applied to Agriculture (BIOAGRO), Federal University of Viçosa, Viçosa-MG 36570-900, Brazil
| | - Alessandra Alves de Souza
- Citrus Research Center "Sylvio Moreira", Agronomic Institute (IAC), Cordeiropolis-SP 13490-970, Brazil
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27
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Jiang H, Wang Z, Jia AQ. Methyl gallate from Camellia nitidissima Chi flowers reduces quorum sensing related virulence and biofilm formation against Aeromonas hydrophila. Biofouling 2024; 40:64-75. [PMID: 38373897 DOI: 10.1080/08927014.2024.2316611] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Accepted: 02/02/2024] [Indexed: 02/21/2024]
Abstract
Aeromonas hydrophila, a Gram-negative zoonotic bacterium, causes high mortality in fish farming and immunocompromised patients. This study aimed to extract methyl gallate (MG) from the flowers of Camellia nitidissima Chi and evaluate its potential as a quorum sensing inhibitor (QSI) against Aeromonas hydrophila SHAe 115. MG reduced QS-associated virulence factors, including hemolysis, protease, and lipase, while impairing swimming motility and biofilm formation. Additionally, MG down-regulated positive regulatory genes (ahyR, fleQ) and up-regulated negative regulators (litR, fleN). This highlights MG's promise as a potent QSI for A. hydrophila SHAe 115, advancing strategies against infections in aquaculture and human health.
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Affiliation(s)
- Huan Jiang
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing, China
- Hainan General Hospital, Hainan Affiliated Hospital of Hainan Medical University, Haikou, China
| | - Zhennan Wang
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing, China
| | - Ai-Qun Jia
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing, China
- Hainan General Hospital, Hainan Affiliated Hospital of Hainan Medical University, Haikou, China
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Schwartzkopf CM, Taylor VL, Groleau MC, Faith DR, Schmidt AK, Lamma TL, Brooks DM, Déziel E, Maxwell KL, Secor PR. Inhibition of PQS signaling by the Pf bacteriophage protein PfsE enhances viral replication in Pseudomonas aeruginosa. Mol Microbiol 2024; 121:116-128. [PMID: 38038061 PMCID: PMC10842821 DOI: 10.1111/mmi.15202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 10/24/2023] [Accepted: 11/16/2023] [Indexed: 12/02/2023]
Abstract
Quorum sensing, a bacterial signaling system that coordinates group behaviors as a function of cell density, plays an important role in regulating viral (phage) defense mechanisms in bacteria. The opportunistic pathogen Pseudomonas aeruginosa is a model system for the study of quorum sensing. P. aeruginosa is also frequently infected by Pf prophages that integrate into the host chromosome. Upon induction, Pf phages suppress host quorum sensing systems; however, the physiological relevance and mechanism of suppression are unknown. Here, we identify the Pf phage protein PfsE as an inhibitor of Pseudomonas Quinolone Signal (PQS) quorum sensing. PfsE binds to the host protein PqsA, which is essential for the biosynthesis of the PQS signaling molecule. Inhibition of PqsA increases the replication efficiency of Pf virions when infecting a new host and when the Pf prophage switches from lysogenic replication to active virion replication. In addition to inhibiting PQS signaling, our prior work demonstrates that PfsE also binds to PilC and inhibits type IV pili extension, protecting P. aeruginosa from infection by type IV pili-dependent phages. Overall, this work suggests that the simultaneous inhibition of PQS signaling and type IV pili by PfsE may be a viral strategy to suppress host defenses to promote Pf replication while at the same time protecting the susceptible host from competing phages.
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Affiliation(s)
| | | | - Marie-Christine Groleau
- Centre Armand-Frappier Santé Biotechnologie, Institut National de la Recherche Scientifique (INRS), Laval, Québec, Canada
| | - Dominick R. Faith
- Division of Biological Sciences, University of Montana, Missoula, Montana, USA
| | - Amelia K. Schmidt
- Division of Biological Sciences, University of Montana, Missoula, Montana, USA
| | - Tyrza L. Lamma
- Division of Biological Sciences, University of Montana, Missoula, Montana, USA
| | - Diane M. Brooks
- Division of Biological Sciences, University of Montana, Missoula, Montana, USA
| | - Eric Déziel
- Centre Armand-Frappier Santé Biotechnologie, Institut National de la Recherche Scientifique (INRS), Laval, Québec, Canada
| | - Karen L. Maxwell
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| | - Patrick R. Secor
- Division of Biological Sciences, University of Montana, Missoula, Montana, USA
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29
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Carneiro DG, Pereira Aguilar A, Mantovani HC, Mendes TADO, Vanetti MCD. The quorum sensing molecule C12-HSL promotes biofilm formation and increases adrA expression in Salmonella Enteritidis under anaerobic conditions. Biofouling 2024; 40:14-25. [PMID: 38254292 DOI: 10.1080/08927014.2024.2305385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Accepted: 01/07/2024] [Indexed: 01/24/2024]
Abstract
Acyl-homoserine lactones (AHLs) are quorum-sensing signaling molecules in Gram-negative bacteria and positively regulate biofilm formation in Salmonella under specific conditions. In this study, biofilm formation in Salmonella enterica was evaluated at 28 and 37 °C, under aerobic and anaerobic conditions. Additionally, the influence of the N-dodecanoyl-DL-homoserine lactone (C12-HSL) on biofilm formation and the expression of genes related to the synthesis of structural components, regulation, and quorum sensing was assessed under anaerobiosis at 28 and 37 °C. Biofilm formation was found not to be influenced by the atmospheric conditions at 28 °C. However, it was reduced at 37 °C under anaerobiosis. C12-HSL enhanced biofilm formation at 37 °C under anaerobiosis and increased the expression of the adrA and luxS genes, suggesting an increase in c-di-GMP, a second messenger that controls essential physiological functions in bacteria. These results provide new insights into the regulation of biofilm formation in Salmonella under anaerobic conditions.
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Affiliation(s)
| | - Ananda Pereira Aguilar
- Department of Biochemistry and Molecular Biology, Universidade Federal de Viçosa (UFV), Viçosa, Brazil
| | - Hilário Cuquetto Mantovani
- Department of Microbiology, Universidade Federal de Viçosa (UFV), Viçosa, Brazil
- Department of Animal and Dairy Sciences, University of WI, Madison, USA
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30
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Kostylev M, Smalley NE, Chao MH, Greenberg EP. Relationship of the transcription factor MexT to quorum sensing and virulence in Pseudomonas aeruginosa. J Bacteriol 2023; 205:e0022623. [PMID: 38032211 PMCID: PMC10729655 DOI: 10.1128/jb.00226-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Accepted: 11/09/2023] [Indexed: 12/01/2023] Open
Abstract
IMPORTANCE Pseudomonas aeruginosa is an opportunistic bacterial pathogen. Many of its virulence genes are regulated by quorum sensing (QS), a form of cell-to-cell communication. P. aeruginosa QS consists of three interlinked circuits, LasI-R, Rhl-R, and Pseudomonas quinolone signal (PQS). Additionally, its QS system is interconnected with other regulatory networks, which help optimize gene expression under variable conditions. The numbers of genes regulated by QS differ substantially among P. aeruginosa strains. We show that a regulatory factor MexT, which is activated in response to certain antibiotics, downregulates the RhlI-R circuit and in turn measurably lowers virulence in a nematode worm infection model. Our findings help understand how existing and future therapeutic interventions for P. aeruginosa infections may impact this bacterium's gene regulation and physiology.
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Affiliation(s)
- Maxim Kostylev
- Department of Microbiology, University of Washington School of Medicine, Seattle, Washington, USA
| | - Nicole E. Smalley
- Department of Microbiology, University of Washington School of Medicine, Seattle, Washington, USA
| | - Man Hou Chao
- Department of Microbiology, University of Washington School of Medicine, Seattle, Washington, USA
| | - E. Peter Greenberg
- Department of Microbiology, University of Washington School of Medicine, Seattle, Washington, USA
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31
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Ding X, Robbe-Masselot C, Fu X, Léonard R, Marsac B, Dauriat CJG, Lepissier A, Rytter H, Ramond E, Dupuis M, Euphrasie D, Dubail I, Schimmich C, Qin X, Parraga J, Leite-de-Moraes M, Ferroni A, Chassaing B, Sermet-Gaudelus I, Charbit A, Coureuil M, Jamet A. Airway environment drives the selection of quorum sensing mutants and promote Staphylococcus aureus chronic lifestyle. Nat Commun 2023; 14:8135. [PMID: 38065959 PMCID: PMC10709412 DOI: 10.1038/s41467-023-43863-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Accepted: 11/22/2023] [Indexed: 12/18/2023] Open
Abstract
Staphylococcus aureus is a predominant cause of chronic lung infections. While the airway environment is rich in highly sialylated mucins, the interaction of S. aureus with sialic acid is poorly characterized. Using S. aureus USA300 as well as clinical isolates, we demonstrate that quorum-sensing dysfunction, a hallmark of S. aureus adaptation, correlates with a greater ability to consume free sialic acid, providing a growth advantage in an air-liquid interface model and in vivo. Furthermore, RNA-seq experiment reveals that free sialic acid triggers transcriptional reprogramming promoting S. aureus chronic lifestyle. To support the clinical relevance of our results, we show the co-occurrence of S. aureus, sialidase-producing microbiota and free sialic acid in the airway of patients with cystic fibrosis. Our findings suggest a dual role for sialic acid in S. aureus airway infection, triggering virulence reprogramming and driving S. aureus adaptive strategies through the selection of quorum-sensing dysfunctional strains.
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Affiliation(s)
- Xiongqi Ding
- Université Paris Cité, INSERM UMR-S1151, CNRS UMR-S8253, Institut Necker Enfants Malades, F75015, Paris, France
| | - Catherine Robbe-Masselot
- Université Lille, CNRS, UMR 8576 - UGSF - Unité de Glycobiologie Structurale et Fonctionnelle, F-59000, Lille, France
| | - Xiali Fu
- Université Paris Cité, INSERM UMR-S1151, CNRS UMR-S8253, Institut Necker Enfants Malades, F75015, Paris, France
| | - Renaud Léonard
- Université Lille, CNRS, UMR 8576 - UGSF - Unité de Glycobiologie Structurale et Fonctionnelle, F-59000, Lille, France
| | - Benjamin Marsac
- Université Lille, CNRS, UMR 8576 - UGSF - Unité de Glycobiologie Structurale et Fonctionnelle, F-59000, Lille, France
| | - Charlene J G Dauriat
- INSERM U1016, CNRS UMR8104, Université Paris Cité, Team «Mucosal Microbiota in Chronic Inflammatory Diseases», F75014, Paris, France
| | - Agathe Lepissier
- Université Paris Cité, INSERM UMR-S1151, CNRS UMR-S8253, Institut Necker Enfants Malades, F75015, Paris, France
| | - Héloïse Rytter
- Université Paris Cité, INSERM UMR-S1151, CNRS UMR-S8253, Institut Necker Enfants Malades, F75015, Paris, France
| | - Elodie Ramond
- Genoscope, UMR8030, Laboratory of Systems & Synthetic Biology (LISSB), Xenome team, F91057, Evry, France
| | - Marion Dupuis
- Université Paris Cité, INSERM UMR-S1151, CNRS UMR-S8253, Institut Necker Enfants Malades, F75015, Paris, France
| | - Daniel Euphrasie
- Université Paris Cité, INSERM UMR-S1151, CNRS UMR-S8253, Institut Necker Enfants Malades, F75015, Paris, France
| | - Iharilalao Dubail
- Université Paris Cité, INSERM UMR-S1151, CNRS UMR-S8253, Institut Necker Enfants Malades, F75015, Paris, France
| | - Cécile Schimmich
- Anses, Laboratory of Animal Health in Normandy, Physiopathology and epidemiology of equine diseases (PhEED), RD 675, F14430, Goustranville, France
| | - Xiaoquan Qin
- Université Paris Cité, Institut de physique du globe de Paris, CNRS, F75005, Paris, France
| | - Jessica Parraga
- Department of Clinical Microbiology, Necker-Enfants Malades Hospital, AP-HP Centre Université de Paris Cité, F75015, Paris, France
| | - Maria Leite-de-Moraes
- Université Paris Cité, INSERM UMR-S1151, CNRS UMR-S8253, Institut Necker Enfants Malades, F75015, Paris, France
| | - Agnes Ferroni
- Department of Clinical Microbiology, Necker-Enfants Malades Hospital, AP-HP Centre Université de Paris Cité, F75015, Paris, France
| | - Benoit Chassaing
- INSERM U1016, CNRS UMR8104, Université Paris Cité, Team «Mucosal Microbiota in Chronic Inflammatory Diseases», F75014, Paris, France
| | - Isabelle Sermet-Gaudelus
- Université Paris Cité, INSERM UMR-S1151, CNRS UMR-S8253, Institut Necker Enfants Malades, F75015, Paris, France
| | - Alain Charbit
- Université Paris Cité, INSERM UMR-S1151, CNRS UMR-S8253, Institut Necker Enfants Malades, F75015, Paris, France
| | - Mathieu Coureuil
- Université Paris Cité, INSERM UMR-S1151, CNRS UMR-S8253, Institut Necker Enfants Malades, F75015, Paris, France.
| | - Anne Jamet
- Université Paris Cité, INSERM UMR-S1151, CNRS UMR-S8253, Institut Necker Enfants Malades, F75015, Paris, France.
- Department of Clinical Microbiology, Necker-Enfants Malades Hospital, AP-HP Centre Université de Paris Cité, F75015, Paris, France.
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32
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Simanek KA, Schumacher ML, Mallery CP, Shen S, Li L, Paczkowski JE. Quorum-sensing synthase mutations re-calibrate autoinducer concentrations in clinical isolates of Pseudomonas aeruginosa to enhance pathogenesis. Nat Commun 2023; 14:7986. [PMID: 38042853 PMCID: PMC10693556 DOI: 10.1038/s41467-023-43702-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Accepted: 11/17/2023] [Indexed: 12/04/2023] Open
Abstract
Quorum sensing is a mechanism of bacterial communication that controls virulence gene expression. Pseudomonas aeruginosa regulates virulence via two synthase/transcription factor receptor pairs: LasI/R and RhlI/R. LasR is considered the master transcriptional regulator of quorum sensing, as it upregulates rhlI/R. However, clinical isolates often have inactivating mutations in lasR, while maintaining Rhl-dependent signaling. We sought to understand how quorum sensing progresses in isolates with lasR mutations, specifically via activation of RhlR. We find that clinical isolates with lasR inactivating mutations often harbor concurrent mutations in rhlI. Using ultra-high-performance liquid chromatography coupled with high-resolution mass spectrometry, we discover that strains lacking lasR overproduce the RhlI-synthesized autoinducer and that RhlI variants re-calibrate autoinducer concentrations to wild-type levels, restoring virulent phenotypes. These findings provide a mechanism for the plasticity of quorum sensing progression in an acute infection niche.
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Affiliation(s)
- Kayla A Simanek
- Department of Biomedical Sciences, University at Albany, School of Public Health, Albany, New York, 12201, USA
| | - Megan L Schumacher
- Department of Biomedical Sciences, University at Albany, School of Public Health, Albany, New York, 12201, USA
| | - Caleb P Mallery
- Department of Biomedical Sciences, University at Albany, School of Public Health, Albany, New York, 12201, USA
| | - Stella Shen
- Division of Genetics, Wadsworth Center, New York State Department of Health, Albany, New York, 12208, USA
| | - Lingyun Li
- Division of Environmental Health Sciences, Wadsworth Center, New York State Department of Health, Albany, New York, 12208, USA
| | - Jon E Paczkowski
- Department of Biomedical Sciences, University at Albany, School of Public Health, Albany, New York, 12201, USA.
- Division of Genetics, Wadsworth Center, New York State Department of Health, Albany, New York, 12208, USA.
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33
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Li Y, Yan J, Li J, Xue X, Wang Y, Cao B. A novel quorum sensing regulator LuxT contributes to the virulence of Vibrio cholerae. Virulence 2023; 14:2274640. [PMID: 37908129 PMCID: PMC10621291 DOI: 10.1080/21505594.2023.2274640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Accepted: 10/18/2023] [Indexed: 11/02/2023] Open
Abstract
Vibrio cholerae is a waterborne bacterium that primarily infects the human intestine and causes cholera fatality. Quorum sensing (QS) negatively regulates the expression of V. cholerae virulence gene. However, the primary associated mechanisms remain undetermined. This investigation identified a new QS regulator from the TetR family, LuxT, which increases V. cholerae virulence by directly inhibiting hapR expression. HapR is a master QS regulator that suppresses virulence cascade expression. The expression of luxT increased 4.8-fold in the small intestine of infant mice than in Luria-Bertani broth. ΔluxT mutant strain revealed a substantial defect in the colonizing ability of the small intestines. At low cell densities, the expression level of hapR was upregulated by luxT deletion, suggesting that LuxT can suppress hapR transcription. The electrophoretic mobility shift analysis revealed that LuxT directly binds to the hapR promoter region. Furthermore, luxT expression was upregulated by the two-component system ArcB/ArcA, which responses to changes in oxygen levels in response to the host's small intestine's anaerobic signals. In conclusion, this research reveals a novel cell density-mediated virulence regulation pathway and contributes to understanding the complex association between V. cholerae virulence and QS signals. This evidence furnishes new insights for future studies on cholerae's pathogenic mechanisms.
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Affiliation(s)
- Yuehua Li
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, China
- Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Nankai University, Tianjin, China
- Tianjin Key Laboratory of Microbial Functional Genomics, TEDA College, Nankai University, Tianjin, China
| | - Junxiang Yan
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, China
- Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Nankai University, Tianjin, China
- Tianjin Key Laboratory of Microbial Functional Genomics, TEDA College, Nankai University, Tianjin, China
| | - Jinghao Li
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, China
- Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Nankai University, Tianjin, China
- Tianjin Key Laboratory of Microbial Functional Genomics, TEDA College, Nankai University, Tianjin, China
| | - Xinke Xue
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, China
- Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Nankai University, Tianjin, China
- Tianjin Key Laboratory of Microbial Functional Genomics, TEDA College, Nankai University, Tianjin, China
| | - Ying Wang
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, China
- Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Nankai University, Tianjin, China
- Tianjin Key Laboratory of Microbial Functional Genomics, TEDA College, Nankai University, Tianjin, China
| | - Boyang Cao
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, China
- Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Nankai University, Tianjin, China
- Tianjin Key Laboratory of Microbial Functional Genomics, TEDA College, Nankai University, Tianjin, China
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34
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Börner J, Friedrich T, Klug G. RNase III participates in control of quorum sensing, pigmentation and oxidative stress resistance in Rhodobacter sphaeroides. Mol Microbiol 2023; 120:874-892. [PMID: 37823424 DOI: 10.1111/mmi.15181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Revised: 09/21/2023] [Accepted: 09/26/2023] [Indexed: 10/13/2023]
Abstract
RNase III is a dsRNA-specific endoribonuclease, highly conserved in bacteria and eukarya. In this study, we analysed the effects of inactivation of RNase III on the transcriptome and the phenotype of the facultative phototrophic α-proteobacterium Rhodobacter sphaeroides. RNA-seq revealed an unexpectedly high amount of genes with increased expression located directly downstream to the rRNA operons. Chromosomal insertion of additional transcription terminators restored wild type-like expression of the downstream genes, indicating that RNase III may modulate the rRNA transcription termination in R. sphaeroides. Furthermore, we identified RNase III as a major regulator of quorum-sensing autoinducer synthesis in R. sphaeroides. It negatively controls the expression of the autoinducer synthase CerI by reducing cerI mRNA stability. In addition, RNase III inactivation caused altered resistance against oxidative stress and impaired formation of photosynthetically active pigment-protein complexes. We also observed an increase in the CcsR small RNAs that were previously shown to promote resistance to oxidative stress. Taken together, our data present interesting insights into RNase III-mediated regulation and expand the knowledge on the function of this important enzyme in bacteria.
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Affiliation(s)
- Janek Börner
- Institute of Microbiology and Molecular Biology, Justus-Liebig-University Giessen, Giessen, Germany
| | - Tobias Friedrich
- Biomedical Informatics and Systems Medicine, Justus-Liebig-University Giessen, Giessen, Germany
- Institute of Biochemistry, Justus-Liebig-University Giessen, Giessen, Germany
| | - Gabriele Klug
- Institute of Microbiology and Molecular Biology, Justus-Liebig-University Giessen, Giessen, Germany
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35
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Yin L, Wang Y, Xiang S, Xu K, Wang B, Jia AQ. Tyramine, one quorum sensing inhibitor, reduces pathogenicity and restores tetracycline susceptibility in Burkholderia cenocepacia. Biochem Pharmacol 2023; 218:115906. [PMID: 37951366 DOI: 10.1016/j.bcp.2023.115906] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Revised: 09/22/2023] [Accepted: 11/01/2023] [Indexed: 11/14/2023]
Abstract
Burkholderia cenocepacia is an opportunistic respiratory pathogen of particular relevance to patients with cystic fibrosis (CF), primarily regulating its biological functions and virulence factors through two quorum sensing (QS) systems (CepI/R and CciI/R). The highly persistent incidence of multidrug resistant Burkholderia cenocepacia poses a global threat to public health. In this study, we investigated the effects of tyramine, one biogenic amine, on the QS systems of Burkholderia cenocepacia. Genetic and biochemical analyses revealed that tyramine inhibited the production of N-hexanoyl-homoserine (AHL) signaling molecules (C8-HSL and C6-HSL) by blocking the CepI/R and CciI/R systems. As a result, the inhibition of QS systems leads to reduced production of various virulence factors, such as biofilm formation, extracellular polysaccharides, lipase, and swarming motility. Notably, as a potential quorum sensing inhibitor, tyramine exhibits low toxicity in vivo in Galleria mellonella larvae and is well characterized by Lipinski's five rules. It also shows high gastrointestinal absorption and the ability to cross the blood-brain barrier according to SwissADME database and ProTox-II server. Additionally, tyramine was found to enhance the efficacy of tetracycline in reducing the infectivity of Burkholderia cenocepacia in Galleria mellonella larvae infection model. Therefore, tyramine could be a promising candidate for combination therapy with traditional antimicrobials to improve their effectiveness against Burkholderia cenocepacia.
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Affiliation(s)
- Lujun Yin
- Hainan General Hospital, Hainan Affiliated Hospital of Hainan Medical University, Haikou 570311, China; Key Laboratory of Tropical Biological Resources of Ministry of Education, School of Pharmaceutical Sciences, Hainan University, Haikou 570228, China
| | - Yingjie Wang
- Key Laboratory of Tropical Biological Resources of Ministry of Education, School of Pharmaceutical Sciences, Hainan University, Haikou 570228, China
| | - Shiliang Xiang
- Key Laboratory of Tropical Biological Resources of Ministry of Education, School of Pharmaceutical Sciences, Hainan University, Haikou 570228, China
| | - Kaizhong Xu
- Key Laboratory of Tropical Biological Resources of Ministry of Education, School of Pharmaceutical Sciences, Hainan University, Haikou 570228, China
| | - Bo Wang
- Hainan General Hospital, Hainan Affiliated Hospital of Hainan Medical University, Haikou 570311, China
| | - Ai-Qun Jia
- Hainan General Hospital, Hainan Affiliated Hospital of Hainan Medical University, Haikou 570311, China.
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Xu M, Lyu Y, Cheng K, Zhang B, Cai Z, Chen G, Zhou J. Interactions between quorum sensing/quorum quenching and virulence genes may affect coral health by regulating symbiotic bacterial community. Environ Res 2023; 238:117221. [PMID: 37775014 DOI: 10.1016/j.envres.2023.117221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 09/11/2023] [Accepted: 09/21/2023] [Indexed: 10/01/2023]
Abstract
Quorum sensing (QS) and quorum quenching (QQ) are two antagonistic processes that may regulate the composition, function and structure of bacterial community. In coral holobiont, autoinducers signaling mediate the communication pathways between interspecies and intraspecies bacteria, which regulate the expression of the virulence factors that can damage host health. However, under environmental stressors, the interaction between the QS/QQ gene and virulence factors and their role in the bacterial communities and coral bleaching is still not fully clear. To address this question, here, metagenomics method was used to examine the profile of QS/QQ and virulence genes from a deeply sequenced microbial database, obtained from three bleached and non-bleached corals species. The prediction of bacterial genes of bleached samples involved in functional metabolic pathways were remarkably decreased, and the bacterial community structure on bleached samples was significantly different compared to non-bleached samples. The distribution and significant difference in QS/QQ and virulence genes were also carried out. We found that Proteobacteria was dominant bacteria among all samples, and AI-1 system is widespread within this group of bacteria. The identified specific genes consistently exhibited a trend of increased pathogenicity in bleached corals relative to non-bleached corals. The abundance of pathogenicity-associated QS genes, including bapA, pfoA and dgcB genes, were significantly increased in bleached corals and can encode the protein of biofilm formation and the membrane damaging toxins promoting pathogenic adhesion and infection. Similarly, the virulence genes, such as superoxide dismutase (Mn-SOD gene), metalloproteinase (yme1, yydH and zmpB), glycosidases (malE, malF, malG, and malK) and LodAB (lodB) genes significantly increased. Conversely, QQ genes that inhibit QS activity and virulence factors to defense the pathogens, including blpA, lsrK, amiE, aprE and gmuG showed a significant decrease in bleached groups. Furthermore, the significant correlations were found among virulence, QS/QQ genes, and coral associated bacterial community, and the virulence genes interact with key QS/QQ genes, directly or indirectly influence symbiotic bacterial communities homeostasis, thereby impacting coral health. It suggested that the functional and structural divergence in the symbiont bacteria may be partially attribute to the interplay, involving interactions among the host, bacterial communication signal systems, and bacterial virulence factors. In conclusion, these data helped to reveal the characteristic behavior of coral symbiotic bacteria, and facilitated a better understanding of bleaching mechanism from a chemical ecological perspective.
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Affiliation(s)
- Meiting Xu
- School of Environment, Harbin Institute of Technology, Harbin, 150090, PR China; School of Marine Science and Technology, Harbin Institute of Technology (Weihai), Weihai, 264209, Shandong Province, PR China
| | - Yihua Lyu
- Nansha Islands Coral Reef Ecosystem National Observation and Research Station, Guangzhou, 510300, PR China
| | - Keke Cheng
- Shenzhen Public Platform for Screening and Application of Marine Microbial Resources, Institute for Ocean Engineering, Shenzhen International Graduate School, Tsinghua University, Shenzhen, 518055, PR China
| | - Boya Zhang
- Shenzhen Public Platform for Screening and Application of Marine Microbial Resources, Institute for Ocean Engineering, Shenzhen International Graduate School, Tsinghua University, Shenzhen, 518055, PR China
| | - Zhonghua Cai
- Shenzhen Public Platform for Screening and Application of Marine Microbial Resources, Institute for Ocean Engineering, Shenzhen International Graduate School, Tsinghua University, Shenzhen, 518055, PR China
| | - Guofu Chen
- School of Environment, Harbin Institute of Technology, Harbin, 150090, PR China; School of Marine Science and Technology, Harbin Institute of Technology (Weihai), Weihai, 264209, Shandong Province, PR China.
| | - Jin Zhou
- Shenzhen Public Platform for Screening and Application of Marine Microbial Resources, Institute for Ocean Engineering, Shenzhen International Graduate School, Tsinghua University, Shenzhen, 518055, PR China.
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37
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Zhang C, Liu M, Wu Y, Li X, Zhang C, Call DR, Liu M, Zhao Z. ArcB orchestrates the quorum-sensing system to regulate type III secretion system 1 in Vibrio parahaemolyticus. Gut Microbes 2023; 15:2281016. [PMID: 37982663 PMCID: PMC10841015 DOI: 10.1080/19490976.2023.2281016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Accepted: 11/05/2023] [Indexed: 11/21/2023] Open
Abstract
In many Vibrio species, virulence is regulated by quorum sensing, which is regulated by a complex, multichannel, two-component phosphorelay circuit. Through this circuit, sensor kinases transmit sensory information to the phosphotransferase LuxU via a phosphotransfer mechanism, which in turn transmits the signal to the response regulator LuxO. For Vibrio parahaemolyticus, type III secretion system 1 (T3SS1) is required for cytotoxicity, but it is unclear how quorum sensing regulates T3SS1 expression. Herein, we report that a hybrid histidine kinase, ArcB, instead of LuxU, and sensor kinase LuxQ and response regulator LuxO, collectively orchestrate T3SS1 expression in V. parahaemolyticus. Under high oxygen conditions, LuxQ can interact with ArcB directly and phosphorylates the Hpt domain of ArcB. The Hpt domain of ArcB phosphorylates the downstream response regulator LuxO instead of ArcA. LuxO then activates transcription of the T3SS1 gene cluster. Under hypoxic conditions, ArcB autophosphorylates and phosphorylates ArcA, whereas ArcA does not participate in regulating the expression of T3SS1. Our data provides evidence of an alternative regulatory path involving the quorum sensing phosphorelay and adds another layer of understanding about the environmental regulation of gene expression in V. parahaemolyticus.
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Affiliation(s)
- Ce Zhang
- Jiangsu Province Engineering Research Center for Marine Bio-resources Sustainable Utilization, Hohai University, Nanjing, China
- Department of Marine Biology, College of Oceanography, Hohai University, Nanjing, China
| | - Min Liu
- Jiangsu Province Engineering Research Center for Marine Bio-resources Sustainable Utilization, Hohai University, Nanjing, China
- Department of Marine Biology, College of Oceanography, Hohai University, Nanjing, China
| | - Ying Wu
- Jiangsu Province Engineering Research Center for Marine Bio-resources Sustainable Utilization, Hohai University, Nanjing, China
- Department of Marine Biology, College of Oceanography, Hohai University, Nanjing, China
| | - Xixi Li
- Jiangsu Province Engineering Research Center for Marine Bio-resources Sustainable Utilization, Hohai University, Nanjing, China
- Department of Marine Biology, College of Oceanography, Hohai University, Nanjing, China
| | - Chen Zhang
- Jiangsu Province Engineering Research Center for Marine Bio-resources Sustainable Utilization, Hohai University, Nanjing, China
- Department of Marine Biology, College of Oceanography, Hohai University, Nanjing, China
| | - Douglas R. Call
- Paul G. Allen School for Global Health, Washington State University, Pullman, WA, USA
| | - Ming Liu
- Department of Marine Biology, College of Oceanography, Hohai University, Nanjing, China
- Department of Clinical Laboratory, Shenzhen Third People's Hospital, Second Hospital Affiliated to Southern University of Science and Technology, National Clinical Research Center for Infectious Diseases, Shenzhen, Guangdong Province, China
| | - Zhe Zhao
- Jiangsu Province Engineering Research Center for Marine Bio-resources Sustainable Utilization, Hohai University, Nanjing, China
- Department of Marine Biology, College of Oceanography, Hohai University, Nanjing, China
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Keegan NR, Colón Torres NJ, Stringer AM, Prager LI, Brockley MW, McManaman CL, Wade JT, Paczkowski JE. Promoter selectivity of the RhlR quorum-sensing transcription factor receptor in Pseudomonas aeruginosa is coordinated by distinct and overlapping dependencies on C4-homoserine lactone and PqsE. PLoS Genet 2023; 19:e1010900. [PMID: 38064526 PMCID: PMC10732425 DOI: 10.1371/journal.pgen.1010900] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Revised: 12/20/2023] [Accepted: 11/21/2023] [Indexed: 12/21/2023] Open
Abstract
Quorum sensing is a mechanism of bacterial cell-cell communication that relies on the production and detection of small molecule autoinducers, which facilitate the synchronous expression of genes involved in group behaviors, such as virulence factor production and biofilm formation. The Pseudomonas aeruginosa quorum sensing network consists of multiple interconnected transcriptional regulators, with the transcription factor, RhlR, acting as one of the main drivers of quorum sensing behaviors. RhlR is a LuxR-type transcription factor that regulates its target genes when bound to its cognate autoinducer, C4-homoserine lactone, which is synthesized by RhlI. RhlR function is also regulated by the metallo-β-hydrolase enzyme, PqsE. We recently showed that PqsE binds RhlR to alter its affinity for promoter DNA, a new mechanism of quorum-sensing receptor activation. Here, we perform ChIP-seq analyses of RhlR to map the binding of RhlR across the P. aeruginosa genome, and to determine the impact of C4-homoserine lactone and PqsE on RhlR binding to different sites across the P. aeruginosa genome. We identify 40 RhlR binding sites, all but three of which are associated with genes known to be regulated by RhlR. C4-homoserine lactone is required for maximal binding of RhlR to many of its DNA sites. Moreover, C4-homoserine lactone is required for maximal RhlR-dependent transcription activation from all sites, regardless of whether it impacts RhlR binding to DNA. PqsE is required for maximal binding of RhlR to many DNA sites, with similar effects on RhlR-dependent transcription activation from those sites. However, the effects of PqsE on RhlR specificity are distinct from those of C4-homoserine lactone, and PqsE is sufficient for RhlR binding to some DNA sites in the absence of C4-homoserine lactone. Together, C4-homoserine lactone and PqsE are required for RhlR binding at the large majority of its DNA sites. Thus, our work reveals three distinct modes of activation by RhlR: i) when RhlR is unbound by autoinducer but bound by PqsE, ii) when RhlR is bound by autoinducer but not bound by PqsE, and iii) when RhlR is bound by both autoinducer and PqsE, establishing a stepwise mechanism for the progression of the RhlR-RhlI-PqsE quorum sensing pathway in P. aeruginosa.
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Affiliation(s)
- Nicholas R. Keegan
- Department of Biomedical Sciences, University at Albany, School of Public Health, Albany, New York, United States of America
| | - Nathalie J. Colón Torres
- Division of Genetics, Wadsworth Center, New York State Department of Health, Albany, New York, United States of America
| | - Anne M. Stringer
- Division of Genetics, Wadsworth Center, New York State Department of Health, Albany, New York, United States of America
| | - Lia I. Prager
- Division of Genetics, Wadsworth Center, New York State Department of Health, Albany, New York, United States of America
- Department of Biological Sciences, University at Albany, Albany, New York, United States of America
| | - Matthew W. Brockley
- Division of Genetics, Wadsworth Center, New York State Department of Health, Albany, New York, United States of America
- Department of Biological Sciences, University at Albany, Albany, New York, United States of America
| | - Charity L. McManaman
- Department of Biomedical Sciences, University at Albany, School of Public Health, Albany, New York, United States of America
| | - Joseph T. Wade
- Department of Biomedical Sciences, University at Albany, School of Public Health, Albany, New York, United States of America
- Division of Genetics, Wadsworth Center, New York State Department of Health, Albany, New York, United States of America
| | - Jon E. Paczkowski
- Department of Biomedical Sciences, University at Albany, School of Public Health, Albany, New York, United States of America
- Division of Genetics, Wadsworth Center, New York State Department of Health, Albany, New York, United States of America
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Wilkening RV, Langouët-Astrié C, Severn MM, Federle MJ, Horswill AR. Identifying genetic determinants of Streptococcus pyogenes-host interactions in a murine intact skin infection model. Cell Rep 2023; 42:113332. [PMID: 37889753 PMCID: PMC10841832 DOI: 10.1016/j.celrep.2023.113332] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 09/12/2023] [Accepted: 10/06/2023] [Indexed: 10/29/2023] Open
Abstract
Streptococcus pyogenes is an obligate human pathobiont associated with many disease states. Here, we present a model of S. pyogenes infection using intact murine epithelium. We were able to perform RNA sequencing to evaluate genetic changes undertaken by both the bacterium and host at 5 and 24 h post-infection. Analysis of these genomic data demonstrate that S. pyogenes undergoes genetic adaptation to successfully infect the murine epithelium, including changes to metabolism and activation of the Rgg2/Rgg3 quorum-sensing (QS) system. Subsequent experiments demonstrate that an intact Rgg2/Rgg3 QS cascade is necessary to establish a stable superficial skin infection. QS cascade activation results in increased murine morbidity and bacterial burden on the skin. This phenotype is associated with gross changes to the murine skin and with evidence of inflammation. These experiments offer a method to investigate S. pyogenes-epithelial interactions and demonstrate that a well-studied QS pathway is critical to a persistent infection.
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Affiliation(s)
- Reid V Wilkening
- Section of Pediatric Critical Care Medicine, Department of Pediatrics, University of Colorado School of Medicine, Aurora, CO 80045, USA; Department of Microbiology and Immunology, University of Colorado School of Medicine, Aurora, CO 80045, USA.
| | - Christophe Langouët-Astrié
- Section of Pulmonary Sciences and Critical Care, Department of Medicine, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Morgan M Severn
- Department of Microbiology and Immunology, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Michael J Federle
- Department of Pharmaceutical Sciences, University of Illinois Chicago, Chicago, IL 60607, USA
| | - Alexander R Horswill
- Department of Microbiology and Immunology, University of Colorado School of Medicine, Aurora, CO 80045, USA; Department of Veterans Affairs, Eastern Colorado Healthcare System, Aurora, CO 80045, USA.
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Green MJ, Murray EJ, Williams P, Ghaemmaghami AM, Aylott JW, Williams PM. Modelled-Microgravity Reduces Virulence Factor Production in Staphylococcus aureus through Downregulation of agr-Dependent Quorum Sensing. Int J Mol Sci 2023; 24:15997. [PMID: 37958979 PMCID: PMC10648752 DOI: 10.3390/ijms242115997] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Revised: 10/27/2023] [Accepted: 10/27/2023] [Indexed: 11/15/2023] Open
Abstract
Bacterial contamination during space missions is problematic for human health and damages filters and other vital support systems. Staphylococcus aureus is both a human commensal and an opportunistic pathogen that colonizes human tissues and causes acute and chronic infections. Virulence and colonization factors are positively and negatively regulated, respectively, by bacterial cell-to-cell communication (quorum sensing) via the agr (accessory gene regulator) system. When cultured under low-shear modelled microgravity conditions (LSMMG), S. aureus has been reported to maintain a colonization rather than a pathogenic phenotype. Here, we show that the modulation of agr expression via reduced production of autoinducing peptide (AIP) signal molecules was responsible for this behavior. In an LSMMG environment, the S. aureus strains JE2 (methicillin-resistant) and SH1000 (methicillin-sensitive) both exhibited reduced cytotoxicity towards the human leukemia monocytic cell line (THP-1) and increased fibronectin binding. Using S. aureus agrP3::lux reporter gene fusions and mass spectrometry to quantify the AIP concentrations, the activation of agr, which depends on the binding of AIP to the transcriptional regulator AgrC, was delayed in the strains with an intact autoinducible agr system. This was because AIP production was reduced under these growth conditions compared with the ground controls. Under LSMMG, S. aureus agrP3::lux reporter strains that cannot produce endogenous AIPs still responded to exogenous AIPs. Provision of exogenous AIPs to S. aureus USA300 during microgravity culture restored the cytotoxicity of culture supernatants for the THP-1 cells. These data suggest that microgravity does not affect AgrC-AIP interactions but more likely the generation of AIPs.
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Affiliation(s)
- Macauley J. Green
- School of Pharmacy, University of Nottingham, University Park, Nottingham NG7 2RD, UK; (M.J.G.)
| | - Ewan J. Murray
- Biodiscovery Institute and School of Life Sciences, University of Nottingham, University Park, Nottingham NG7 2RD, UK (P.W.)
| | - Paul Williams
- Biodiscovery Institute and School of Life Sciences, University of Nottingham, University Park, Nottingham NG7 2RD, UK (P.W.)
| | - Amir M. Ghaemmaghami
- School of Life Sciences, University of Nottingham, University Park, Nottingham NG7 2RD, UK
| | - Jonathan W. Aylott
- School of Pharmacy, University of Nottingham, University Park, Nottingham NG7 2RD, UK; (M.J.G.)
| | - Philip M. Williams
- School of Pharmacy, University of Nottingham, University Park, Nottingham NG7 2RD, UK; (M.J.G.)
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Li L, Guan W, Fan Y, He Q, Guo D, Yuan A, Xing Q, Wang Y, Ma Z, Ni J, Chen J, Zhou Q, Zhong Y, Li J, Zhang H. Zinc/carbon nanomaterials inhibit antibiotic resistance genes by affecting quorum sensing and microbial community in cattle manure production. Bioresour Technol 2023; 387:129648. [PMID: 37572887 DOI: 10.1016/j.biortech.2023.129648] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 08/02/2023] [Accepted: 08/05/2023] [Indexed: 08/14/2023]
Abstract
This study used metagenomic sequencing to examine the effects of carbon-based zinc oxide nanoparticles (CZnONPs) and graphene-based zinc oxide nanoparticles (GZnONPs) on quorum sensing (QS), antibiotic resistance genes (ARGs) and microbial community changes during cattle manure production. The manure zinc content was significantly reduced in GZnONPs group. In the QS pathway, the autoinducer gene increases significantly in Control group, while the transporter and repressor genes experience a substantial increase in CZnONPs group. These results contributed to the significantly decreased the abundance of ARGs in GZnONPs group. The co-occurrence network analysis revealed a correlation between core ARGs and QS-related KEGG Orthology or ARGs' hosts, indicating that the selective pressure of zinc influences microbial QS, forming a unique ARG pattern in in vivo anaerobic fermentation. These findings suggest that implementing nutritional regulation in farming practices can serve as a preventive measure to mitigate the potential transmission of ARGs resulting from livestock waste.
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Affiliation(s)
- Lizhi Li
- College of Life Science and Resources and Environment, Yichun University, Yi Chun 336000, China
| | - Weikun Guan
- College of Life Science and Resources and Environment, Yichun University, Yi Chun 336000, China
| | - Yihao Fan
- College of Life Science and Resources and Environment, Yichun University, Yi Chun 336000, China
| | - Qin He
- College of Life Sciences, Nanchang Normal University, Nanchang 330032, China
| | - Dongsheng Guo
- College of Life Science and Resources and Environment, Yichun University, Yi Chun 336000, China
| | - An Yuan
- College of Life Science and Resources and Environment, Yichun University, Yi Chun 336000, China
| | - Qingfeng Xing
- College of Life Science and Resources and Environment, Yichun University, Yi Chun 336000, China
| | - Yang Wang
- College of Life Science and Resources and Environment, Yichun University, Yi Chun 336000, China
| | - Ziqin Ma
- College of Life Science and Resources and Environment, Yichun University, Yi Chun 336000, China
| | - Jian Ni
- College of Life Science and Resources and Environment, Yichun University, Yi Chun 336000, China
| | - Jia Chen
- College of Life Science and Resources and Environment, Yichun University, Yi Chun 336000, China
| | - Qilong Zhou
- College of Life Science and Resources and Environment, Yichun University, Yi Chun 336000, China
| | - Yuhong Zhong
- College of Life Science and Resources and Environment, Yichun University, Yi Chun 336000, China
| | - Jiating Li
- College of Life Science and Resources and Environment, Yichun University, Yi Chun 336000, China
| | - Haibo Zhang
- College of Life Science and Resources and Environment, Yichun University, Yi Chun 336000, China.
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Takemura C, Senuma W, Tsuzuki M, Terazawa Y, Inoue K, Sato M, Kiba A, Ohnishi K, Kai K, Hikichi Y. The transcription regulator ChpA affects the global transcriptome including quorum sensing-dependent genes in Ralstonia pseudosolanacearum strain OE1-1. Mol Plant Pathol 2023; 24:1370-1384. [PMID: 37452484 PMCID: PMC10576176 DOI: 10.1111/mpp.13374] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2023] [Accepted: 06/26/2023] [Indexed: 07/18/2023]
Abstract
The gram-negative plant-pathogenic β-proteobacterium Ralstonia pseudosolanacearum strain OE1-1 produces methyl 3-hydroxymyristate as a quorum sensing (QS) signal through methyltransferase PhcB and senses the chemical via the sensor histidine kinase PhcS. This leads to activation of the LysR family transcription regulator PhcA, which regulates the genes (QS-dependent genes) responsible for QS-dependent phenotypes, including virulence. The transcription regulator ChpA, which possesses a response regulator receiver domain and also a hybrid sensor histidine kinase/response regulator phosphore-acceptor domain but lacks a DNA-binding domain, is reportedly involved in QS-dependent biofilm formation and virulence of R. pseudosolanacearum strain GMI1000. To explore the function of ChpA in QS of OE1-1, we generated a chpA-deletion mutant (ΔchpA) and revealed that the chpA deletion leads to significantly altered QS-dependent phenotypes. Furthermore, ΔchpA exhibited a loss in its infectivity in xylem vessels of tomato plant roots, losing virulence on tomato plants, similar to the phcA-deletion mutant (ΔphcA). Transcriptome analysis showed that the transcript levels of phcB, phcQ, phcR, and phcA in ΔchpA were comparable to those in OE1-1. However, the transcript levels of 89.9% and 88.9% of positively and negatively QS-dependent genes, respectively, were significantly altered in ΔchpA compared with OE1-1. Furthermore, the transcript levels of these genes in ΔchpA were positively correlated with those in ΔphcA. Together, our results suggest that ChpA is involved in the regulation of these QS-dependent genes, thereby contributing to the behaviour in host plant roots and virulence of OE1-1.
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Affiliation(s)
- Chika Takemura
- Faculty of Agriculture and Marine ScienceKochi UniversityNankokuJapan
- Present address:
Kochi Prefectural Agriculture Research CenterNankokuJapan
| | - Wakana Senuma
- Faculty of Agriculture and Marine ScienceKochi UniversityNankokuJapan
- Present address:
Central Research Institute, Ishihara Sangyo Kaisha, Ltd.KusatsuJapan
| | - Masayuki Tsuzuki
- Faculty of Agriculture and Marine ScienceKochi UniversityNankokuJapan
| | - Yuki Terazawa
- Faculty of Agriculture and Marine ScienceKochi UniversityNankokuJapan
- Present address:
Kumamoto Experimental Station, Sumika Agrotech Co., Ltd.KikuchiJapan
| | - Kanako Inoue
- Research Center for Ultra‐High Voltage Electron MicroscopyOsaka UniversityIbarakiJapan
- Present address:
Division of Biological Sciences Plant Immunity, Nara Institute of Science and TechnologyIkomaJapan
| | - Masanao Sato
- Graduate School of AgricultureHokkaido UniversitySapporoJapan
| | - Akinori Kiba
- Faculty of Agriculture and Marine ScienceKochi UniversityNankokuJapan
| | - Kouhei Ohnishi
- Faculty of Agriculture and Marine ScienceKochi UniversityNankokuJapan
| | - Kenji Kai
- Graduate School of AgricultureOsaka Metropolitan UniversitySakaiJapan
| | - Yasufumi Hikichi
- Faculty of Agriculture and Marine ScienceKochi UniversityNankokuJapan
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Venturi V, Špacapan M, Ristović N, Bez C. RsaM: a unique dominant regulator of AHL quorum sensing in bacteria. Microbiology (Reading) 2023; 169:001417. [PMID: 38010341 PMCID: PMC10710839 DOI: 10.1099/mic.0.001417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Accepted: 11/07/2023] [Indexed: 11/29/2023]
Abstract
Quorum sensing (QS) in proteobacteria is a mechanism to control gene expression orchestrated by the LuxI/LuxR protein family pair, which produces and responds to N-acyl homoserine lactone (AHL) diffusible signal molecules. QS is often regarded as a cell density response via the sensing of/response to the concentrations of AHLs, which are constantly basally produced by bacterial cells. The luxI/R systems, however, undergo supra-regulation in response to external stimuli and many regulators have been implicated in controlling QS in bacteria, although it remains unclear how most of these regulators and cues contribute to the QS response. One regulator, called RsaM, has been reported in a few proteobacterial species to have a stringent role in the control of AHL QS. RsaMs are small, in the range of 140-170 aa long, and are found in several genera, principally in Burkholderia and Acinetobacter. The gene encoding RsaM is always located as an independent transcriptional unit, situated adjacent to QS luxI and/or luxR loci. One of the most remarkable aspects of RsaM is its uniqueness; it does not fall into any of the known bacterial regulatory families and it possesses a distinct and novel fold that does not exhibit binding affinity for nucleic acids or AHLs. RsaM stands out as a distinctive regulator in bacteria, as it is likely to have an important ecological role, as well as unravelling a novel way of gene regulation in bacteria.
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Affiliation(s)
- Vittorio Venturi
- International Centre for Genetic Engineering and Biotechnology, Trieste, Italy
| | - Mihael Špacapan
- International Centre for Genetic Engineering and Biotechnology, Trieste, Italy
| | - Nemanja Ristović
- International Centre for Genetic Engineering and Biotechnology, Trieste, Italy
| | - Cristina Bez
- International Centre for Genetic Engineering and Biotechnology, Trieste, Italy
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Li X, Wang G, Guo Q, Cui B, Wang M, Song S, Yang L, Deng Y. Membrane-enclosed Pseudomonas quinolone signal attenuates bacterial virulence by interfering with quorum sensing. Appl Environ Microbiol 2023; 89:e0118423. [PMID: 37796010 PMCID: PMC10617430 DOI: 10.1128/aem.01184-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Accepted: 08/07/2023] [Indexed: 10/06/2023] Open
Abstract
Outer membrane vesicle (OMV)-delivered Pseudomonas quinolone signal (PQS) plays a critical role in cell-cell communication in Pseudomonas aeruginosa. However, the functions and mechanisms of membrane-enclosed PQS in interspecies communication in microbial communities are not clear. Here, we demonstrate that PQS delivered by both OMVs from P. aeruginosa and liposome reduces the competitiveness of Burkholderia cenocepacia, which usually shares the same niche in the lungs of cystic fibrosis patients, by interfering with quorum sensing (QS) in B. cenocepacia through the LysR-type regulator ShvR. Intriguingly, we found that ShvR regulates the production of the QS signals cis-2-dodecenoic acid (BDSF) and N-acyl homoserine lactone (AHL) by directly binding to the promoters of signal synthase-encoding genes. Perception of PQS influences the regulatory activity of ShvR and thus ultimately reduces QS signal production and virulence in B. cenocepacia. Our findings provide insights into the interspecies communication mediated by the membrane-enclosed QS signal among bacterial species residing in the same microbial community.IMPORTANCEQuorum sensing (QS) is a ubiquitous cell-to-cell communication mechanism. Previous studies showed that Burkholderia cenocepacia mainly employs cis-2-dodecenoic acid (BDSF) and N-acyl homoserine lactone (AHL) QS systems to regulate biological functions and virulence. Here, we demonstrate that Pseudomonas quinolone signal (PQS) delivered by outer membrane vesicles from Pseudomonas aeruginosa or liposome attenuates B. cenocepacia virulence by targeting the LysR-type regulator ShvR, which regulates the production of the QS signals BDSF and AHL in B. cenocepacia. Our results not only suggest the important roles of membrane-enclosed PQS in interspecies and interkingdom communications but also provide a new perspective on the use of functional nanocarriers loaded with QS inhibitors for treating pathogen infections.
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Affiliation(s)
- Xia Li
- School of Pharmaceutical Sciences (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Sun Yat-sen University, Shenzhen, Guangdong, China
| | - Gerun Wang
- School of Pharmaceutical Sciences (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Sun Yat-sen University, Shenzhen, Guangdong, China
| | - Quan Guo
- School of Pharmaceutical Sciences (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Sun Yat-sen University, Shenzhen, Guangdong, China
| | - Binbin Cui
- School of Pharmaceutical Sciences (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Sun Yat-sen University, Shenzhen, Guangdong, China
| | - Mingfang Wang
- School of Pharmaceutical Sciences (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Sun Yat-sen University, Shenzhen, Guangdong, China
| | - Shihao Song
- School of Pharmaceutical Sciences (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Sun Yat-sen University, Shenzhen, Guangdong, China
- School of Pharmaceutical Sciences, Hainan University, Haikou, Hainan, China
| | - Liang Yang
- School of Medicine, Southern University of Science and Technology, Shenzhen, Guangdong, China
| | - Yinyue Deng
- School of Pharmaceutical Sciences (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Sun Yat-sen University, Shenzhen, Guangdong, China
- School of Pharmaceutical Sciences, Hainan University, Haikou, Hainan, China
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Shanks RMQ, Atta S, Stella NA, Sundar-Raj CV, Romanowski JE, Grewal AS, Shanks HQ, Mumper SM, Dhaliwal DK, Mammen A, Callaghan JD, Calvario RC, Romanowski EG, Kowalski RP, Zegans ME, Jhanji V. A rise in the frequency of lasR mutant Pseudomonas aeruginosa among keratitis isolates between 1993 and 2021. Front Cell Infect Microbiol 2023; 13:1286842. [PMID: 38029269 PMCID: PMC10651084 DOI: 10.3389/fcimb.2023.1286842] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Accepted: 10/16/2023] [Indexed: 12/01/2023] Open
Abstract
Introduction Pseudomonas aeruginosa causes vision threatening keratitis. The LasR transcription factor regulates virulence factors in response to the quorum sensing molecule N-3-oxo-dodecanoyl-L-homoserine lactone. P. aeruginosa isolates with lasR mutations are characterized by an iridescent high sheen phenotype caused by a build-up of 2-heptyl-4-quinolone. A previous study demonstrated 22% (n=101) of P. aeruginosa keratitis isolates from India between 2010 and 2016 were sheen positive lasR mutants, and the sheen phenotype correlated with worse clinical outcomes for patients. In this study, a longitudinal collection of P. aeruginosa keratitis isolates from Eastern North America were screened for lasR mutations by the sheen phenotype and sequencing of the lasR gene. Methods Keratitis isolates (n=399) were classified by sheen phenotype. The lasR gene was cloned from a subset of isolates, sequenced, and tested for loss of function or dominant-negative status based on an azocasein protease assay. A retrospective chart review compared outcomes of keratitis patients infected by sheen positive and negative isolates. Results A significant increase in sheen positive isolates was observed between 1993 and 2021. Extracellular protease activity was reduced among the sheen positive isolates and a defined lasR mutant. Cloned lasR alleles from the sheen positive isolates were loss of function or dominant negative and differed in sequence from previously reported ocular lasR mutant alleles. Retrospective analysis of patient information suggested significantly better visual outcomes for patients infected by sheen positive isolates. Discussion These results indicate an increase in lasR mutations among keratitis isolates in the United States and suggest that endemic lasR mutants can cause keratitis.
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Affiliation(s)
- Robert M. Q. Shanks
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Sarah Atta
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Nicholas A. Stella
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Chollapadi V. Sundar-Raj
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - John E. Romanowski
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Arman S. Grewal
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Hazel Q. Shanks
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Sonya M. Mumper
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Deepinder K. Dhaliwal
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Alex Mammen
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Jake D. Callaghan
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Rachel C. Calvario
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Eric G. Romanowski
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Regis P. Kowalski
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Michael E. Zegans
- Department of Surgery, Geisel School of Medicine at Dartmouth, Hanover, NH, United States
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, NH, United States
| | - Vishal Jhanji
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
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Cai W, Liao H, Lu M, Zhou X, Cheng X, Staehelin C, Dai W. New Evolutionary Insights into RpoA: A Novel Quorum Sensing Reprograming Factor in Pseudomonas aeruginosa. Mol Biol Evol 2023; 40:msad203. [PMID: 37708386 PMCID: PMC10566545 DOI: 10.1093/molbev/msad203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Revised: 08/19/2023] [Accepted: 08/22/2023] [Indexed: 09/16/2023] Open
Abstract
Quorum-sensing (QS) coordinates the expression of virulence factors in Pseudomonas aeruginosa, an opportunistic pathogen known for causing severe infections in immunocompromised patients. QS has a master regulator, the lasR gene, but in clinical settings, P. aeruginosa isolates have been found that are QS-active but LasR-null. In this study, we developed an experimental evolutionary approach to identify additional QS-reprogramming determinants. We began the study with a LasR-null mutant with an extra copy of mexT, a transcriptional regulator gene that is known to be able to reprogram QS in laboratory LasR-null strains. In this strain, spontaneous single mexT mutations are expected to have no or little phenotypic consequences. Using this novel method, which we have named "targeted gene duplication followed by mutant screening", we identified QS-active revertants with mutations in genes other than mexT. One QS-active revertant had a point mutation in rpoA, a gene encoding the α-subunit of RNA polymerase. QS activation in this mutant was found to be associated with the downregulated expression of mexEF-oprN efflux pump genes. Our study therefore uncovers a new functional role for RpoA in regulating QS activity. Our results indicate that a RpoA-dependent regulatory circuit controlling the expression of the mexEF-oprN operon is critical for QS-reprogramming. In conclusion, our study reports on the identification of non-MexT proteins associated with QS-reprogramming in a laboratory strain, shedding light on possible QS activation mechanisms in clinical P. aeruginosa isolates.
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Affiliation(s)
- Wenjie Cai
- Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou, China
- College of Plant Protection, Integrative Microbiology Research Center, South China Agricultural University, Guangzhou, China
| | - Huimin Liao
- Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou, China
- College of Plant Protection, Integrative Microbiology Research Center, South China Agricultural University, Guangzhou, China
| | - Mingqi Lu
- Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou, China
- College of Plant Protection, Integrative Microbiology Research Center, South China Agricultural University, Guangzhou, China
| | - Xiangting Zhou
- Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou, China
- College of Plant Protection, Integrative Microbiology Research Center, South China Agricultural University, Guangzhou, China
| | - Xiaoyan Cheng
- Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou, China
- College of Plant Protection, Integrative Microbiology Research Center, South China Agricultural University, Guangzhou, China
| | - Christian Staehelin
- State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Weijun Dai
- Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou, China
- College of Plant Protection, Integrative Microbiology Research Center, South China Agricultural University, Guangzhou, China
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Moraskie M, Roshid MHO, O'Connor G, Artola Zavala T, Dikici E, Zingg JM, Deo S, Daunert S. Engineered biosensors for the quorum sensing molecule 3,5-dimethyl-pyrazine-2-ol (DPO) reveal its presence in humans, animals, and bacterial species beyond Vibrio cholerae. Biosens Bioelectron 2023; 237:115494. [PMID: 37419073 DOI: 10.1016/j.bios.2023.115494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Revised: 06/13/2023] [Accepted: 06/20/2023] [Indexed: 07/09/2023]
Abstract
A biosensor was engineered to enable the study of the novel quorum sensing molecule (QSM), 3,5-dimethylpyrazin-2-ol (DPO), employed by Vibrio cholerae to regulate biofilm formation and virulence factor production. Investigations into bacterial quorum sensing (QS), a form of communication based on the production and detection of QSMs to coordinate gene expression in a population dependent manner, offer a unique window to study the molecular underpinnings of microbial behavior and host interactions. Herein, we report the construction of an engineered microbial whole-cell bioluminescent biosensing system that incorporates the recognition of the VqmA regulatory protein of Vibrio cholerae with the bioluminescent reporting signal of luciferase for the selective, sensitive, stable, and reproducible detection of DPO in a variety of samples. Importantly, using our newly developed biosensor our studies demonstrate the detection of DPO in rodent and human samples. Employing our developed biosensor should help enable elucidation of microbial behavior at the molecular level and its impact in health and disease.
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Affiliation(s)
- Michael Moraskie
- Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL, 33136, USA; The Dr. John T. Macdonald Foundation Biomedical Nanotechnology Institute-BioNIUM, University of Miami, Miami, FL, 33136, USA
| | - Md Harun Or Roshid
- Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL, 33136, USA; The Dr. John T. Macdonald Foundation Biomedical Nanotechnology Institute-BioNIUM, University of Miami, Miami, FL, 33136, USA; Department of Chemistry, University of Miami, Miami, FL, 33146, USA
| | - Gregory O'Connor
- Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL, 33136, USA; The Dr. John T. Macdonald Foundation Biomedical Nanotechnology Institute-BioNIUM, University of Miami, Miami, FL, 33136, USA
| | - Teresa Artola Zavala
- Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL, 33136, USA; The Dr. John T. Macdonald Foundation Biomedical Nanotechnology Institute-BioNIUM, University of Miami, Miami, FL, 33136, USA; Universidad Francisco de Vitoria, Madrid, Spain
| | - Emre Dikici
- Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL, 33136, USA; The Dr. John T. Macdonald Foundation Biomedical Nanotechnology Institute-BioNIUM, University of Miami, Miami, FL, 33136, USA
| | - Jean-Marc Zingg
- Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL, 33136, USA; The Dr. John T. Macdonald Foundation Biomedical Nanotechnology Institute-BioNIUM, University of Miami, Miami, FL, 33136, USA
| | - Sapna Deo
- Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL, 33136, USA; The Dr. John T. Macdonald Foundation Biomedical Nanotechnology Institute-BioNIUM, University of Miami, Miami, FL, 33136, USA
| | - Sylvia Daunert
- Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL, 33136, USA; The Dr. John T. Macdonald Foundation Biomedical Nanotechnology Institute-BioNIUM, University of Miami, Miami, FL, 33136, USA; Department of Chemistry, University of Miami, Miami, FL, 33146, USA; The Miami Clinical and Translational Science Institute, University of Miami, Miami, FL, 33146, USA; Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, FL, 33146, USA.
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Edwards AN, McBride SM. The RgaS-RgaR two-component system promotes Clostridioides difficile sporulation through a small RNA and the Agr1 system. PLoS Genet 2023; 19:e1010841. [PMID: 37844084 PMCID: PMC10602386 DOI: 10.1371/journal.pgen.1010841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 10/26/2023] [Accepted: 10/02/2023] [Indexed: 10/18/2023] Open
Abstract
The ability to form a dormant spore is essential for the survival of the anaerobic pathogen, Clostridioides difficile, outside of the mammalian gastrointestinal tract. The initiation of sporulation is governed by the master regulator of sporulation, Spo0A, which is activated by phosphorylation. Multiple sporulation factors control Spo0A phosphorylation; however, this regulatory pathway is not well defined in C. difficile. We discovered that RgaS and RgaR, a conserved orphan histidine kinase and orphan response regulator, function together as a cognate two-component regulatory system to directly activate transcription of several genes. One of these targets, agrB1D1, encodes gene products that synthesize and export a small quorum-sensing peptide, AgrD1, which positively influences expression of early sporulation genes. Another target, a small regulatory RNA now known as SpoZ, impacts later stages of sporulation through a small hypothetical protein and an additional, unknown regulatory mechanism(s). Unlike Agr systems in many organisms, AgrD1 does not activate the RgaS-RgaR two-component system, and thus, is not responsible for autoregulating its own production. Altogether, we demonstrate that C. difficile utilizes a conserved two-component system that is uncoupled from quorum-sensing to promote sporulation through two distinct regulatory pathways.
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Affiliation(s)
- Adrianne N. Edwards
- Department of Microbiology and Immunology, Emory University School of Medicine, Emory Antibiotic Resistance Center, Atlanta, Georgia, United States of America
| | - Shonna M. McBride
- Department of Microbiology and Immunology, Emory University School of Medicine, Emory Antibiotic Resistance Center, Atlanta, Georgia, United States of America
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Quiroz-Morales SE, Muriel-Millán LF, Ponce-Soto GY, González-Valdez A, Castillo-Juárez I, Servín-González L, Soberón-Chávez G. Pseudomonas aeruginosa strains belonging to phylogroup 3 frequently exhibit an atypical quorum sensing response: the case of MAZ105, a tomato rhizosphere isolate. Microbiology (Reading) 2023; 169:001401. [PMID: 37819040 PMCID: PMC10634362 DOI: 10.1099/mic.0.001401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Accepted: 10/03/2023] [Indexed: 10/13/2023]
Abstract
Pseudomonas aeruginosa is a widespread γ-proteobacterium and an important opportunistic pathogen. The genetically diverse P. aeruginosa phylogroup 3 strains are characterized by producing the pore-forming ExlA toxin and by their lack of a type III secretion system. However, like all strains of this species, they produce several virulence-associated traits, such as elastase, rhamnolipids and pyocyanin, which are regulated by quorum sensing (QS). The P. aeruginosa QS response comprises three systems (Las, Rhl and Pqs, respectively) that hierarchically regulate these virulence factors. The Pqs QS system is composed of the PqsR transcriptional factor, which, coupled with the alkyl-quinolones HHQ or PQS, activates the transcription of the pqsABCDE operon. The products of the first four genes of this operon produce HHQ, which is then converted to PQS by PqsH, while PqsE forms a complex with RhlR and stabilizes it. In this study we report that mutations affecting the Pqs system are particularly common in phylogroup 3 strains. To better understand QS in phylogroup 3 strains we studied strain MAZ105 isolated from tomato rhizosphere and showed that it contains mutations in the central QS transcriptional regulator, LasR, and in the gene encoding the PqsA enzyme involved in the synthesis of PQS. However, it can still produce QS-regulated virulence factors and is virulent in Galleria mellonella and mildly pathogenic in the mouse abscess/necrosis model; our results show that this may be due to the expression of pqsE from a different PqsR-independent promoter than the pqsA promoter. Our results indicate that using anti-virulence therapy based on targeting the PQS system will not be effective against infections by P. aeruginosa phylogroup 3 strains.
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Affiliation(s)
- Sara E. Quiroz-Morales
- Departamento de Biología Molecular y Biotecnología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad Universitaria, Apdo, Postal 70228, C. P. 04510, CDMX, Mexico
| | - Luis Felipe Muriel-Millán
- Departamento de Microbiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Av. Universidad 2001, Col. Chamilpa, Cuernavaca, Morelos CP 62210, Mexico
| | - Gabriel Y. Ponce-Soto
- Microbial Paleogenomics Unit, Department of Genomes and Genetics, Pasteur Institute, 75015 Paris, France
| | - Abigail González-Valdez
- Departamento de Biología Molecular y Biotecnología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad Universitaria, Apdo, Postal 70228, C. P. 04510, CDMX, Mexico
| | - Israel Castillo-Juárez
- Laboratorio de Investigación y Aplicación de Fitoquímicos Bioactivos, Colegio de Postgraduados, 56230, Campus Montecillo, Texcoco, Mexico
| | - Luis Servín-González
- Departamento de Biología Molecular y Biotecnología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad Universitaria, Apdo, Postal 70228, C. P. 04510, CDMX, Mexico
| | - Gloria Soberón-Chávez
- Departamento de Biología Molecular y Biotecnología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad Universitaria, Apdo, Postal 70228, C. P. 04510, CDMX, Mexico
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50
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Gutzmann DJ, Kramer JJ, Toomey BM, Boone CHT, Atkin AL, Nickerson KW. Transcriptional regulation of the synthesis and secretion of farnesol in the fungus Candida albicans: examination of the Homann transcription regulator knockout collection. G3 (Bethesda) 2023; 13:jkad172. [PMID: 37522561 PMCID: PMC10542173 DOI: 10.1093/g3journal/jkad172] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2023] [Revised: 07/18/2023] [Accepted: 07/21/2023] [Indexed: 08/01/2023]
Abstract
Candida albicans is an efficient colonizer of human gastrointestinal tracts and skin and is an opportunistic pathogen. C. albicans exhibits morphological plasticity, and the ability to switch between yeast and filamentous morphologies is associated with virulence. One regulator of this switch is the quorum sensing molecule farnesol that is produced by C. albicans throughout growth. However, the synthesis, secretion, regulation, and turnover of farnesol are not fully understood. To address this, we used our improved farnesol assay to screen a transcription regulator knockout library for differences in farnesol accumulation in whole cultures, pellets, and supernatants. All screened mutants produced farnesol and they averaged 9.2× more farnesol in the pellet than the supernatant. Nineteen mutants had significant differences with ten mutants producing more farnesol than their SN152+ wild-type control strain while nine produced less. Seven mutants exhibited greater secretion of farnesol while two exhibited less. We examined the time course for farnesol accumulation in six mutants with the greatest accumulation differences and found that those differences persisted throughout growth and they were not time dependent. Significantly, two high-accumulating mutants did not exhibit the decay in farnesol levels during stationary phase characteristic of wild-type C. albicans, suggesting that a farnesol modification/degradation mechanism is absent in these mutants. Identifying these transcriptional regulators provides new insight into farnesol's physiological functions regarding cell cycle progression, white-opaque switching, yeast-mycelial dimorphism, and response to cellular stress.
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Affiliation(s)
- Daniel J Gutzmann
- School of Biological Sciences, University of Nebraska, Lincoln, NE 68588, USA
| | - Jaxon J Kramer
- School of Biological Sciences, University of Nebraska, Lincoln, NE 68588, USA
| | - Brigid M Toomey
- School of Biological Sciences, University of Nebraska, Lincoln, NE 68588, USA
| | - Cory H T Boone
- School of Biological Sciences, University of Nebraska, Lincoln, NE 68588, USA
| | - Audrey L Atkin
- School of Biological Sciences, University of Nebraska, Lincoln, NE 68588, USA
| | - Kenneth W Nickerson
- School of Biological Sciences, University of Nebraska, Lincoln, NE 68588, USA
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