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Jonblat S, As-sadi F, El Khoury A, Badr N, Kallassy M, Chokr A. Determining the dispersion time in Staphylococcus epidermidis biofilm using physical and molecular approaches. Heliyon 2024; 10:e32389. [PMID: 38975180 PMCID: PMC11225768 DOI: 10.1016/j.heliyon.2024.e32389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2024] [Revised: 05/31/2024] [Accepted: 06/03/2024] [Indexed: 07/09/2024] Open
Abstract
Despite being an innocuous commensal of human skin and mucous membranes, Staphylococcus epidermidis, infects surgical wounds and causes infections through biofilm formation. This study evaluates, in a time-dependent experiment, the self-dispersion of S. epidermidis CIP 444 biofilm when formed on borosilicate glass (hydrophilic) and polystyrene (hydrophobic) surfaces, using physical and molecular approaches. During a seven-day period of incubation, absorbance measurement revealed a drop in biofilm optical density on both studied surfaces on day 4 (0.043-0.035 nm/cm2, polystyrene), (0.06-0.053 nm/cm2, borosilicate glass). Absorbance results were correlated with crystal violet staining that showed a clear detachment from day 4. The blue color increases again on day 7, with an increase in biofilm optical density indicating the regeneration of the biofilm. Changes in gene expression in the S. epidermidis biofilm were assessed using a real-time reverse transcription-polymerase chain reaction. High expression of agr genes was detected on days 4 and 5, confirming our supposition of dispersion in this period, autolysin genes like atlE1 and aae were upregulated from day 3 until day 6 and the genes responsible for slime production and biofilm accumulation, were upregulated on days 4, 5, and 6 (ica ADBC) and on days 5, 6 and 7 (aap), indicating a dual process taking place. These findings suggest that S. epidermidis CIP 444 biofilms disperse at day 4 and reform at day 7. Over the course of the seven-day investigation, 2-ΔΔCt results showed that some genes in the biofilm were dramatically enhanced while others were significantly decreased as compared to planktonic ones.
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Affiliation(s)
- Suzanne Jonblat
- Research Laboratory of Microbiology (RLM), Department of Life and Earth Sciences, Faculty of Sciences I, Lebanese University, Hadat Campus, Beirut, Lebanon
- Functional Genomic and Proteomic Laboratory, Faculté des Sciences, Université Saint-Joseph de Beyrouth, Campus des Sciences et Technologies, Mar Roukos, Matn, Lebanon
- Centre d'Analyses et de Recherche (CAR), Unité de Recherche Technologies et Valorisation Agro-Alimentaire (UR-TVA), Faculté des Sciences, Université Saint-Joseph de Beyrouth, Campus des Sciences et Technologies, Mar Roukos, Matn, Lebanon
- Platform of Research and Analysis in Environmental Sciences (PRASE), Doctoral School of Sciences and Technologies, Lebanese University, Hadat Campus, Beirut, Lebanon
| | - Falah As-sadi
- Research Laboratory of Microbiology (RLM), Department of Life and Earth Sciences, Faculty of Sciences I, Lebanese University, Hadat Campus, Beirut, Lebanon
- Department of Plant Production, Faculty of Agriculture and Veterinary Medicine, Lebanese University, Beirut, 999095, Lebanon
| | - Andre El Khoury
- Centre d'Analyses et de Recherche (CAR), Unité de Recherche Technologies et Valorisation Agro-Alimentaire (UR-TVA), Faculté des Sciences, Université Saint-Joseph de Beyrouth, Campus des Sciences et Technologies, Mar Roukos, Matn, Lebanon
| | - Neressa Badr
- Research Laboratory of Microbiology (RLM), Department of Life and Earth Sciences, Faculty of Sciences I, Lebanese University, Hadat Campus, Beirut, Lebanon
| | - Mireille Kallassy
- Functional Genomic and Proteomic Laboratory, Faculté des Sciences, Université Saint-Joseph de Beyrouth, Campus des Sciences et Technologies, Mar Roukos, Matn, Lebanon
| | - Ali Chokr
- Research Laboratory of Microbiology (RLM), Department of Life and Earth Sciences, Faculty of Sciences I, Lebanese University, Hadat Campus, Beirut, Lebanon
- Platform of Research and Analysis in Environmental Sciences (PRASE), Doctoral School of Sciences and Technologies, Lebanese University, Hadat Campus, Beirut, Lebanon
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2
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Eisenbraun EL, Vulpis TD, Prosser BN, Horswill AR, Blackwell HE. Synthetic Peptides Capable of Potent Multigroup Staphylococcal Quorum Sensing Activation and Inhibition in Both Cultures and Biofilm Communities. J Am Chem Soc 2024; 146:15941-15954. [PMID: 38832917 DOI: 10.1021/jacs.4c02694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2024]
Abstract
The pathogen Staphylococcus epidermidis uses a chemical signaling process, i.e., quorum sensing (QS), to form robust biofilms and cause human infection. Many questions remain about QS in S. epidermidis, as it uses this intercellular communication pathway to both negatively and positively regulate virulence traits. Herein, we report synthetic multigroup agonists and antagonists of the S. epidermidis accessory gene regulator (agr) QS system capable of potent superactivation and complete inhibition, respectively. These macrocyclic peptides maintain full efficacy across the three major agr specificity groups, and their activity can be "mode-switched" from agonist to antagonist via subtle residue-specific structural changes. We describe the design and synthesis of these non-native peptides and demonstrate that they can appreciably decrease biofilm formation on abiotic surfaces, underscoring the potential for agr agonism as a route to block S. epidermidis virulence. Additionally, we show that both the S. epidermidis agonists and antagonists are active in S. aureus, another common pathogen with a related agr system, yet only as antagonists. This result not only revealed one of the most potent agr inhibitors known in S. aureus but also highlighted differences in the mechanisms of agr agonism and antagonism between these related bacteria. Finally, our investigations reveal unexpected inhibitory behavior for certain S. epidermidis agr agonists at sub-activating concentrations, an observation that can be leveraged for the design of future probes with enhanced potencies. Together, these peptides provide a powerful tool set to interrogate the role of QS in S. epidermidis infections and in Staphylococcal pathogenicity in general.
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Affiliation(s)
- Emma L Eisenbraun
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Ave., Madison, Wisconsin 53706, United States
| | - Troy D Vulpis
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Ave., Madison, Wisconsin 53706, United States
| | - Brendan N Prosser
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Ave., Madison, Wisconsin 53706, United States
| | - Alexander R Horswill
- Department of Immunology and Microbiology, Anschutz Medical Campus, University of Colorado, Aurora, Colorado 80045, United States
| | - Helen E Blackwell
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Ave., Madison, Wisconsin 53706, United States
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3
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Ou L, Ye B, Sun M, Qi N, Li J, Lv M, Lin X, Cai H, Hu J, Song Y, Chen X, Zhu Y, Yin L, Zhang J, Liao S, Zhang H. Mechanisms of intestinal epithelial cell damage by Clostridiumperfringens. Anaerobe 2024; 87:102856. [PMID: 38609034 DOI: 10.1016/j.anaerobe.2024.102856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 03/31/2024] [Accepted: 04/09/2024] [Indexed: 04/14/2024]
Abstract
Clostridium perfringens, a Gram-positive bacterium, causes intestinal diseases in humans and livestock through its toxins, related to alpha toxin (CPA), beta toxin (CPB), C. perfringens enterotoxin (CPE), epsilon toxin (ETX), Iota toxin (ITX), and necrotic enteritis B-like toxin (NetB). These toxins disrupt intestinal barrier, leading to various cell death mechanisms such as necrosis, apoptosis, and necroptosis. Additionally, non-toxin factors like adhesins and degradative enzymes contribute to virulence by enhancing colonization and survival of C. perfringens. A vicious cycle of intestinal barrier breach, misregulated cell death, and subsequent inflammation is at the heart of chronic inflammatory and infectious gastrointestinal diseases. Understanding these mechanisms is essential for developing targeted therapies against C. perfringens-associated intestinal diseases.
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Affiliation(s)
- Lanxin Ou
- Key Laboratory of Livestock Disease Prevention of Guangdong Province, Key Laboratory of Avian Influenza and Other Major Poultry Diseases Prevention and Control, Ministry of Agriculture and Rural Affairs, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640, China; College of Life Science and Engineering, Foshan University, Foshan, 528225, China
| | - Bijin Ye
- Key Laboratory of Livestock Disease Prevention of Guangdong Province, Key Laboratory of Avian Influenza and Other Major Poultry Diseases Prevention and Control, Ministry of Agriculture and Rural Affairs, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640, China; College of Life Science and Engineering, Foshan University, Foshan, 528225, China
| | - Mingfei Sun
- Key Laboratory of Livestock Disease Prevention of Guangdong Province, Key Laboratory of Avian Influenza and Other Major Poultry Diseases Prevention and Control, Ministry of Agriculture and Rural Affairs, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640, China
| | - Nanshan Qi
- Key Laboratory of Livestock Disease Prevention of Guangdong Province, Key Laboratory of Avian Influenza and Other Major Poultry Diseases Prevention and Control, Ministry of Agriculture and Rural Affairs, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640, China
| | - Juan Li
- Key Laboratory of Livestock Disease Prevention of Guangdong Province, Key Laboratory of Avian Influenza and Other Major Poultry Diseases Prevention and Control, Ministry of Agriculture and Rural Affairs, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640, China
| | - Minna Lv
- Key Laboratory of Livestock Disease Prevention of Guangdong Province, Key Laboratory of Avian Influenza and Other Major Poultry Diseases Prevention and Control, Ministry of Agriculture and Rural Affairs, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640, China
| | - Xuhui Lin
- Key Laboratory of Livestock Disease Prevention of Guangdong Province, Key Laboratory of Avian Influenza and Other Major Poultry Diseases Prevention and Control, Ministry of Agriculture and Rural Affairs, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640, China
| | - Haiming Cai
- Key Laboratory of Livestock Disease Prevention of Guangdong Province, Key Laboratory of Avian Influenza and Other Major Poultry Diseases Prevention and Control, Ministry of Agriculture and Rural Affairs, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640, China
| | - Junjing Hu
- Key Laboratory of Livestock Disease Prevention of Guangdong Province, Key Laboratory of Avian Influenza and Other Major Poultry Diseases Prevention and Control, Ministry of Agriculture and Rural Affairs, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640, China
| | - Yongle Song
- Key Laboratory of Livestock Disease Prevention of Guangdong Province, Key Laboratory of Avian Influenza and Other Major Poultry Diseases Prevention and Control, Ministry of Agriculture and Rural Affairs, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640, China
| | - Xiangjie Chen
- Key Laboratory of Livestock Disease Prevention of Guangdong Province, Key Laboratory of Avian Influenza and Other Major Poultry Diseases Prevention and Control, Ministry of Agriculture and Rural Affairs, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640, China
| | - Yibin Zhu
- Key Laboratory of Livestock Disease Prevention of Guangdong Province, Key Laboratory of Avian Influenza and Other Major Poultry Diseases Prevention and Control, Ministry of Agriculture and Rural Affairs, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640, China
| | - Lijun Yin
- Key Laboratory of Livestock Disease Prevention of Guangdong Province, Key Laboratory of Avian Influenza and Other Major Poultry Diseases Prevention and Control, Ministry of Agriculture and Rural Affairs, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640, China
| | - Jianfei Zhang
- Key Laboratory of Livestock Disease Prevention of Guangdong Province, Key Laboratory of Avian Influenza and Other Major Poultry Diseases Prevention and Control, Ministry of Agriculture and Rural Affairs, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640, China
| | - Shenquan Liao
- Key Laboratory of Livestock Disease Prevention of Guangdong Province, Key Laboratory of Avian Influenza and Other Major Poultry Diseases Prevention and Control, Ministry of Agriculture and Rural Affairs, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640, China.
| | - Haoji Zhang
- College of Life Science and Engineering, Foshan University, Foshan, 528225, China.
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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] [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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5
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Yamaguchi J, Manome T, Hara Y, Yamazaki Y, Nakamura Y, Ishibashi M, Takaya A. Physalin H, physalin B, and isophysalin B suppress the quorum-sensing function of Staphylococcus aureus by binding to AgrA. Front Pharmacol 2024; 15:1365815. [PMID: 38659576 PMCID: PMC11039898 DOI: 10.3389/fphar.2024.1365815] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2024] [Accepted: 03/25/2024] [Indexed: 04/26/2024] Open
Abstract
The virulence of Staphylococcus aureus, including methicillin-resistant S. aureus (MRSA), depends on the expression of toxins and virulence factors controlled by the quorum-sensing (QS) system, encoded on the virulence accessory gene regulator (agr) locus. The aim of this study was to identify a phytochemical that inhibits Agr-QS function and to elucidate its mechanism. We screened 577 compounds and identified physalin H, physalin B, and isophysalin B--phytochemicals belonging to physalins found in plants of the Solanaceae family--as novel Agr-QS modulators. Biological analyses and in vitro protein-DNA binding assays suggested that these physalins suppress gene expression related to the Agr-QS system by inhibiting binding of the key response regulator AgrA to the agr promoters, reducing the function of hemolytic toxins downstream of these genes in MRSA. Furthermore, although physalin F suppressed gene expression in the Agr-QS system, its anti-hemolytic activity was lower than that of physalins H, B, and isophysalin B. Conversely, five physalins isolated from the same plant with the ability to suppress Agr-QS did not reduce bacterial Agr-QS activity but inhibited AgrA binding to DNA in vitro. A docking simulation revealed that physalin interacts with the DNA-binding site of AgrA in three docking states. The carbonyl oxygens at C-1 and C-18 of physalins, which can suppress Agr-QS, were directed to residues N201 and R198 of AgrA, respectively, whereas these carbonyl oxygens of physalins, without Agr-QS suppression activity, were oriented in different directions. Next, 100-ns molecular dynamics simulations revealed that the hydrogen bond formed between the carbonyl oxygen at C-15 of physalins and L186 of AgrA functions as an anchor, sustaining the interaction between the carbonyl oxygen at C-1 of physalins and N201 of AgrA. Thus, these results suggest that physalin H, physalin B, and isophysalin B inhibit the interaction of AgrA with the agr promoters by binding to the DNA-binding site of AgrA, suppressing the Agr-QS function of S. aureus. Physalins that suppress the Agr-QS function are proposed as potential lead compounds in the anti-virulence strategy for MRSA infections.
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Affiliation(s)
- Junpei Yamaguchi
- Department of Infection Control Science, Graduate School of Pharmaceutical Sciences, Chiba University, Chiba, Japan
| | - Teruhisa Manome
- Graduate School of Pharmaceutical Sciences, Chiba University, Chiba, Japan
- Laboratory of Natural Products Chemistry, Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan
| | - Yasumasa Hara
- Graduate School of Pharmaceutical Sciences, Chiba University, Chiba, Japan
- Faculty of Agriculture, Kagawa University, Takamatsu, Japan
| | - Yuriko Yamazaki
- Cutaneous Allergy and Host Defense, Immunology Frontier Research Center, Osaka University, Osaka, Japan
- Department of Dermatology, Graduate School of Medicine, Osaka University, Osaka, Japan
| | - Yuumi Nakamura
- Cutaneous Allergy and Host Defense, Immunology Frontier Research Center, Osaka University, Osaka, Japan
- Department of Dermatology, Graduate School of Medicine, Osaka University, Osaka, Japan
| | - Masami Ishibashi
- Graduate School of Pharmaceutical Sciences, Chiba University, Chiba, Japan
- School of Pharmacy at Fukuoka, International University of Health and Welfare, Okawa, Japan
| | - Akiko Takaya
- Department of Infection Control Science, Graduate School of Pharmaceutical Sciences, Chiba University, Chiba, Japan
- Medical Mycology Research Center, Chiba University, Chiba, Japan
- Plant Molecular Science Center, Chiba University, Chiba, Japan
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6
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Liu A, Garrett S, Hong W, Zhang J. Staphylococcus aureus Infections and Human Intestinal Microbiota. Pathogens 2024; 13:276. [PMID: 38668232 PMCID: PMC11053856 DOI: 10.3390/pathogens13040276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2024] [Revised: 03/18/2024] [Accepted: 03/23/2024] [Indexed: 04/29/2024] Open
Abstract
Staphylococcus aureus (S. aureus) is a common pathogen that can cause many human diseases, such as skin infection, food poisoning, endocarditis, and sepsis. These diseases can be minor infections or life-threatening, requiring complex medical management resulting in substantial healthcare costs. Meanwhile, as the critically ignored "organ," the intestinal microbiome greatly impacts physiological health, not only in gastrointestinal diseases but also in disorders beyond the gut. However, the correlation between S. aureus infection and intestinal microbial homeostasis is largely unknown. Here, we summarized the recent progress in understanding S. aureus infections and their interactions with the microbiome in the intestine. These summarizations will help us understand the mechanisms behind these infections and crosstalk and the challenges we are facing now, which could contribute to preventing S. aureus infections, effective treatment investigation, and vaccine development.
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Affiliation(s)
- Aotong Liu
- Department of Pharmacology & Regenerative Medicine, College of Medicine, University of Illinois Chicago, Chicago, IL 60612, USA;
| | - Shari Garrett
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois Chicago, Chicago, IL 60612, USA;
- Department of Microbiology and Immunology, University of Illinois Chicago, Chicago, IL 60612, USA
| | - Wanqing Hong
- Faculty of Science, University of Waterloo, Waterloo, ON N2L 3G1, Canada;
- School of Chemistry & Chemical Engineering and Materials Sciences, Shandong Normal University, Jinan 250061, China
| | - Jilei Zhang
- Department of Pharmacology & Regenerative Medicine, College of Medicine, University of Illinois Chicago, Chicago, IL 60612, USA;
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7
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Podkowik M, Perault AI, Putzel G, Pountain A, Kim J, Dumont A, Zwack E, 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. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.06.08.544038. [PMID: 37333372 PMCID: PMC10274873 DOI: 10.1101/2023.06.08.544038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/20/2023]
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 increased both respiration and fermentation but decreased ATP levels and growth, suggesting that Δagr cells assume a hyperactive metabolic state in response to reduced 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 (Nox2-/-) 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 Medicine, New York, NY, USA
- Antimicrobial-Resistant Pathogens Program, New York University School of Medicine, New York, NY, USA
| | - Andrew I. Perault
- Antimicrobial-Resistant Pathogens Program, New York University School of Medicine, New York, NY, USA
- Department of Microbiology, NYU Grossman School of Medicine, New York, NY, USA
| | - Gregory Putzel
- Antimicrobial-Resistant Pathogens Program, New York University School of Medicine, New York, NY, USA
- Department of Microbiology, NYU Grossman School of Medicine, New York, NY, USA
- Microbial Computational Genomic Core Lab, NYU Grossman School of Medicine, New York, NY, USA
| | - Andrew Pountain
- Institute for Systems Genetics; NYU Grossman School of Medicine, New York, NY, USA
| | - Jisun Kim
- Department of Pathology, Immunology and Laboratory Medicine, Center for Immunity and Inflammation, Rutgers New Jersey Medical School Cancer Center, Newark, NJ, USA
| | - Ashley Dumont
- Department of Microbiology, NYU Grossman School of Medicine, New York, NY, USA
| | - Erin Zwack
- Department of Microbiology, NYU Grossman School of Medicine, New York, NY, USA
| | - Robert J. Ulrich
- Department of Medicine, Division of Infectious Diseases, NYU Grossman School of Medicine, New York, NY, USA
| | - Theodora K. Karagounis
- Antimicrobial-Resistant Pathogens Program, New York University School of Medicine, New York, NY, USA
- Ronald O. Perelman Department of Dermatology; NYU Grossman School of Medicine, New York, NY, USA
| | - Chunyi Zhou
- Department of Medicine, Division of Infectious Diseases, NYU Grossman School of Medicine, New York, NY, USA
- Antimicrobial-Resistant Pathogens Program, New York University School of Medicine, New York, NY, USA
| | - Andreas F. Haag
- School of Medicine, University of St Andrews, St Andrews, UK
| | - Julia Shenderovich
- Antimicrobial-Resistant Pathogens Program, New York University School of Medicine, New York, NY, USA
- Department of Microbiology, NYU Grossman School of Medicine, New York, NY, USA
| | | | - Junbeom Kwon
- Department of Medicine, Division of Infectious Diseases, NYU Grossman School of Medicine, New York, NY, USA
| | - John Chen
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Anthony R. Richardson
- Department of Microbiology and Molecular Genetics, University of Pittsburgh, Pittsburgh, PA, USA
| | - Jeffrey N. Weiser
- Department of Microbiology, NYU Grossman School of Medicine, New York, NY, USA
| | - Carla R. Nowosad
- Department of Pathology, NYU Grossman School of Medicine, New York, NY, USA
| | - Desmond S. Lun
- Center for Computational and Integrative Biology and Department of Computer Science, Rutgers University, Camden, NJ, USA
| | - Dane Parker
- Department of Pathology, Immunology and Laboratory Medicine, Center for Immunity and Inflammation, Rutgers New Jersey Medical School Cancer Center, Newark, NJ, USA
| | - Alejandro Pironti
- Antimicrobial-Resistant Pathogens Program, New York University School of Medicine, New York, NY, USA
- Department of Microbiology, NYU Grossman School of Medicine, New York, NY, USA
- Microbial Computational Genomic Core Lab, NYU Grossman School of Medicine, New York, NY, USA
| | - Xilin Zhao
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, Fujian Province, China
| | - Karl Drlica
- Public Health Research Institute, New Jersey Medical School, Rutgers University, Newark, NJ, USA
- Department of Microbiology, Biochemistry & Molecular Genetics, New Jersey Medical School, Rutgers University, Newark, NJ, USA
| | - Itai Yanai
- Institute for Systems Genetics; NYU Grossman School of Medicine, New York, NY, USA
- Department of Biochemistry and Molecular Pharmacology, NYU Grossman School of Medicine, New York, NY, USA
| | - Victor J. Torres
- Antimicrobial-Resistant Pathogens Program, New York University School of Medicine, New York, NY, USA
- Department of Microbiology, NYU Grossman School of Medicine, New York, NY, USA
| | - Bo Shopsin
- Department of Medicine, Division of Infectious Diseases, NYU Grossman School of Medicine, New York, NY, USA
- Antimicrobial-Resistant Pathogens Program, New York University School of Medicine, New York, NY, USA
- Department of Microbiology, NYU Grossman School of Medicine, New York, NY, USA
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8
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Jiang JH, Cameron DR, Nethercott C, Aires-de-Sousa M, Peleg AY. Virulence attributes of successful methicillin-resistant Staphylococcus aureus lineages. Clin Microbiol Rev 2023; 36:e0014822. [PMID: 37982596 PMCID: PMC10732075 DOI: 10.1128/cmr.00148-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2023] Open
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) is a leading cause of severe and often fatal infections. MRSA epidemics have occurred in waves, whereby a previously successful lineage has been replaced by a more fit and better adapted lineage. Selection pressures in both hospital and community settings are not uniform across the globe, which has resulted in geographically distinct epidemiology. This review focuses on the mechanisms that trigger the establishment and maintenance of current, dominant MRSA lineages across the globe. While the important role of antibiotic resistance will be mentioned throughout, factors which influence the capacity of S. aureus to colonize and cause disease within a host will be the primary focus of this review. We show that while MRSA possesses a diverse arsenal of toxins including alpha-toxin, the success of a lineage involves more than just producing toxins that damage the host. Success is often attributed to the acquisition or loss of genetic elements involved in colonization and niche adaptation such as the arginine catabolic mobile element, as well as the activity of regulatory systems, and shift metabolism accordingly (e.g., the accessory genome regulator, agr). Understanding exactly how specific MRSA clones cause prolonged epidemics may reveal targets for therapies, whereby both core (e.g., the alpha toxin) and acquired virulence factors (e.g., the Panton-Valentine leukocidin) may be nullified using anti-virulence strategies.
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Affiliation(s)
- Jhih-Hang Jiang
- Department of Microbiology, Infection Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
- Department of Infectious Diseases, The Alfred Hospital and Central Clinical School, Monash University, Melbourne, Victoria, Australia
| | - David R. Cameron
- Department of Biomedical Research, University of Bern, Bern, Switzerland
| | - Cara Nethercott
- Department of Microbiology, Infection Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Marta Aires-de-Sousa
- Laboratory of Molecular Genetics, Institutode Tecnologia Químicae Biológica António Xavier (ITQB-NOVA), Universidade Nova de Lisboa, Oeiras, Portugal
- Escola Superior de Saúde da Cruz Vermelha Portuguesa-Lisboa (ESSCVP-Lisboa), Lisbon, Portugal
| | - Anton Y. Peleg
- Department of Microbiology, Infection Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
- Department of Infectious Diseases, The Alfred Hospital and Central Clinical School, Monash University, Melbourne, Victoria, Australia
- Centre to Impact Antimicrobial Resistance, Monash University, Clayton, Melbourne, Victoria, Australia
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9
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Li H, Jia M, Qi Q, Wang Q. Engineered probiotic Lactobacillus plantarum WCSF I for monitoring and treatment of Staphylococcus aureus infection. Microbiol Spectr 2023; 11:e0182923. [PMID: 37909791 PMCID: PMC10848683 DOI: 10.1128/spectrum.01829-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Accepted: 09/23/2023] [Indexed: 11/03/2023] Open
Abstract
IMPORTANCE Bacterial infection and the emergence of drug-resistant strains are major problems in clinical treatment. Staphylococcus aureus, which typically infects the skin and blood of animals, is also a potential intestinal pathogen that needs to be addressed by the emergence of a new treatment approach. Probiotic therapy is the most likely alternative to antibiotic therapy to solve the problem of bacterial drug resistance in clinical practice. In this study, the engineered Lactobacillus plantarum can not only sense the signal AIP to detect S. aureus but also kill S. aureus by secreting the lysostaphin enzyme. Our strategy employed an Agr quorum-sensing genetic circuit to simultaneously detect and treat pathogenic bacteria, which provided a theoretical possibility for solving practical clinical bacterial infection cases in the future.
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Affiliation(s)
- Haoran Li
- National Glycoengineering Research Center, Shandong University, Qingdao, China
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Minjun Jia
- National Glycoengineering Research Center, Shandong University, Qingdao, China
| | - Qingsheng Qi
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Qian Wang
- National Glycoengineering Research Center, Shandong University, Qingdao, China
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10
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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] [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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11
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Etter D, Jenni C, Edwards V, Greutmann M, Waltenspül T, Tasara T, Johler S. Stress Lowers Staphylococcal Enterotoxin C Production Independently of Agr, SarA, and SigB. J Food Prot 2023; 86:100127. [PMID: 37414283 DOI: 10.1016/j.jfp.2023.100127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2023] [Revised: 06/28/2023] [Accepted: 07/01/2023] [Indexed: 07/08/2023]
Abstract
Staphylococcal enterotoxin C (SEC) can cause staphylococcal food poisoning, one of the most prevalent foodborne intoxications. It is produced by Staphylococcus aureus during growth in the food matrix. While the surrounding bacteria in food matrices usually repress the growth of S.aureus, the organism possesses a remarkable growth advantage under stressful conditions encountered in many foods. Examples for such food matrices are pastry and bakery products with their high sugar content that lowers water availability. While S. aureus can still grow in these challenging environments, it remains unclear how these conditions affect SEC expression. Here, the influence of 30% glucose on sec mRNA in a qPCR assay and SEC protein expression was investigated for the first time in an ELISA. In addition, regulatory knockout mutants Δagr, ΔsarA, and ΔsigB were generated to investigate regulatory gene elements in glucose stress. In five out of seven strains, glucose stress led to a pronounced decrease in sec mRNA transcription and SEC protein levels were substantially lower under glucose stress. It could be shown that key regulatory elements Δagr, ΔsarA, and ΔsigB in strain SAI48 did not contribute to the pronounced downregulation under glucose stress. Based on these findings, glucose effectively lowers SEC synthesis in the food matrix. However, the mechanism by which it acts on toxin expression and regulatory elements in S. aureus remains unclear. Future studies on other regulatory elements and transcriptomics may shed light on the mechanisms.
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Affiliation(s)
- Danai Etter
- Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zurich, Winterthurerstrasse 272, 8057 Zurich, Switzerland; Institute for Food, Nutrition and Health, ETH Zurich, Schmelzbergstrasse 9, 8092 Zurich, Switzerland
| | - Céline Jenni
- Institute for Food, Nutrition and Health, ETH Zurich, Schmelzbergstrasse 9, 8092 Zurich, Switzerland
| | - Veronica Edwards
- Institute for Food, Nutrition and Health, ETH Zurich, Schmelzbergstrasse 9, 8092 Zurich, Switzerland
| | - Mariella Greutmann
- Institute for Food, Nutrition and Health, ETH Zurich, Schmelzbergstrasse 9, 8092 Zurich, Switzerland
| | - Tabea Waltenspül
- Institute for Food, Nutrition and Health, ETH Zurich, Schmelzbergstrasse 9, 8092 Zurich, Switzerland
| | - Taurai Tasara
- Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zurich, Winterthurerstrasse 272, 8057 Zurich, Switzerland
| | - Sophia Johler
- Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zurich, Winterthurerstrasse 272, 8057 Zurich, Switzerland.
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12
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Hsieh RC, Liu R, Burgin DJ, Otto M. Understanding mechanisms of virulence in MRSA: implications for antivirulence treatment strategies. Expert Rev Anti Infect Ther 2023; 21:911-928. [PMID: 37501364 DOI: 10.1080/14787210.2023.2242585] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Accepted: 07/26/2023] [Indexed: 07/29/2023]
Abstract
INTRODUCTION Methicillin-resistant Staphylococcus aureus (MRSA) is a widespread pathogen, often causing recurrent and deadly infections in the hospital and community. Many S. aureus virulence factors have been suggested as potential targets for antivirulence therapy to decrease the threat of diminishing antibiotic availability. Antivirulence methods hold promise due to their adjunctive and prophylactic potential and decreased risk for selective pressure. AREAS COVERED This review describes the dominant virulence mechanisms exerted by MRSA and antivirulence therapeutics that are currently undergoing testing in clinical or preclinical stages. We also discuss the advantages and downsides of several investigational antivirulence approaches, including the targeting of bacterial transporters, host-directed therapy, and quorum-sensing inhibitors. For this review, a systematic search of literature on PubMed, Google Scholar, and Web of Science for relevant search terms was performed in April and May 2023. EXPERT OPINION Vaccine and antibody strategies have failed in clinical trials and could benefit from more basic science-informed approaches. Antivirulence-targeting approaches need to be set up better to meet the requirements of drug development, rather than only providing limited results to provide 'proof-of-principle' translational value of pathogenesis research. Nevertheless, there is great potential of such strategies and potential particular promise for novel probiotic approaches.
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Affiliation(s)
- Roger C Hsieh
- Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases (NIAID), U.S. National Institutes of Health (NIH), Bethesda, Maryland, USA
| | - Ryan Liu
- Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases (NIAID), U.S. National Institutes of Health (NIH), Bethesda, Maryland, USA
| | - Dylan J Burgin
- Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases (NIAID), U.S. National Institutes of Health (NIH), Bethesda, Maryland, USA
| | - Michael Otto
- Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases (NIAID), U.S. National Institutes of Health (NIH), Bethesda, Maryland, USA
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13
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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. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.26.546640. [PMID: 37425791 PMCID: PMC10327067 DOI: 10.1101/2023.06.26.546640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/11/2023]
Abstract
The ability to form a dormant spore is essential for the survival of the anaerobic, gastrointestinal 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 SrsR, impacts later stages of sporulation through an 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, GA, USA
| | - Shonna M. McBride
- Department of Microbiology and Immunology, Emory University School of Medicine, Emory Antibiotic Resistance Center, Atlanta, GA, USA
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14
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Patel H, Rawat S. A genetic regulatory see-saw of biofilm and virulence in MRSA pathogenesis. Front Microbiol 2023; 14:1204428. [PMID: 37434702 PMCID: PMC10332168 DOI: 10.3389/fmicb.2023.1204428] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Accepted: 05/30/2023] [Indexed: 07/13/2023] Open
Abstract
Staphylococcus aureus is one of the most common opportunistic human pathogens causing several infectious diseases. Ever since the emergence of the first methicillin-resistant Staphylococcus aureus (MRSA) strain decades back, the organism has been a major cause of hospital-acquired infections (HA-MRSA). The spread of this pathogen across the community led to the emergence of a more virulent subtype of the strain, i.e., Community acquired Methicillin resistant Staphylococcus aureus (CA-MRSA). Hence, WHO has declared Staphylococcus aureus as a high-priority pathogen. MRSA pathogenesis is remarkable because of the ability of this "superbug" to form robust biofilm both in vivo and in vitro by the formation of polysaccharide intercellular adhesin (PIA), extracellular DNA (eDNA), wall teichoic acids (WTAs), and capsule (CP), which are major components that impart stability to a biofilm. On the other hand, secretion of a diverse array of virulence factors such as hemolysins, leukotoxins, enterotoxins, and Protein A regulated by agr and sae two-component systems (TCS) aids in combating host immune response. The up- and downregulation of adhesion genes involved in biofilm formation and genes responsible for synthesizing virulence factors during different stages of infection act as a genetic regulatory see-saw in the pathogenesis of MRSA. This review provides insight into the evolution and pathogenesis of MRSA infections with a focus on genetic regulation of biofilm formation and virulence factors secretion.
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Affiliation(s)
| | - Seema Rawat
- Microbiology Laboratory, School of Life Sciences, Central University of Gujarat, Gandhinagar, Gujarat, India
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15
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Polaske TJ, West KHJ, Zhao K, Widner DL, York JT, Blackwell HE. Chemical and biomolecular insights into the Staphylococcus aureus agr quorum sensing system: Current progress and ongoing challenges. Isr J Chem 2023; 63:e202200096. [PMID: 38765792 PMCID: PMC11101167 DOI: 10.1002/ijch.202200096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Indexed: 03/19/2023]
Abstract
Staphylococcus aureus is a ubiquitous bacterium that has become a major threat to human health due to its extensive toxin production and tremendous capacity for antibiotic resistance (e.g., MRSA "superbug" infections). Amid a worsening antibiotic resistance crisis, new strategies to combat this deadly microbe that remove the selective pressure of traditional approaches are in high demand. S. aureus utilizes an accessory gene regulator (agr) quorum sensing network to monitor its local cellular population and trigger a devastating communal attack, like an invading horde, once a threshold cell density has been reached. The role of the agr system in a range of disease types is still being unraveled. Herein, we discuss the present-day biochemical understanding of agr along with unresolved details, describe its connection to the progression of infection, and review how chemical strategies have been implemented to study and intercept this signaling pathway. This research is illuminating the potential of agr as an anti-virulence target in S. aureus and should inform the study of similar, yet less studied, agr systems in related bacterial pathogens.
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Affiliation(s)
- Thomas J. Polaske
- Department of Chemistry, University of Wisconsin–Madison, 1101 University Ave., Madison, WI 53706 USA
| | - Korbin H. J. West
- Department of Chemistry, University of Wisconsin–Madison, 1101 University Ave., Madison, WI 53706 USA
| | - Ke Zhao
- Department of Chemistry, University of Wisconsin–Madison, 1101 University Ave., Madison, WI 53706 USA
| | - Danielle L. Widner
- Department of Chemistry, University of Wisconsin–Madison, 1101 University Ave., Madison, WI 53706 USA
| | - Jordan T. York
- Department of Chemistry, University of Wisconsin–Madison, 1101 University Ave., Madison, WI 53706 USA
| | - Helen E. Blackwell
- Department of Chemistry, University of Wisconsin–Madison, 1101 University Ave., Madison, WI 53706 USA
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16
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Condinho M, Carvalho B, Cruz A, Pinto SN, Arraiano CM, Pobre V. The role of RNA regulators, quorum sensing and c-di-GMP in bacterial biofilm formation. FEBS Open Bio 2023; 13:975-991. [PMID: 35234364 PMCID: PMC10240345 DOI: 10.1002/2211-5463.13389] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 02/15/2022] [Accepted: 02/28/2022] [Indexed: 11/10/2022] Open
Abstract
Biofilms provide an ecological advantage against many environmental stressors, such as pH and temperature, making it the most common life-cycle stage for many bacteria. These protective characteristics make eradication of bacterial biofilms challenging. This is especially true in the health sector where biofilm formation on hospital or patient equipment, such as respirators, or catheters, can quickly become a source of anti-microbial resistant strains. Biofilms are complex structures encased in a self-produced polymeric matrix containing numerous components such as polysaccharides, proteins, signalling molecules, extracellular DNA and extracellular RNA. Biofilm formation is tightly controlled by several regulators, including quorum sensing (QS), cyclic diguanylate (c-di-GMP) and small non-coding RNAs (sRNAs). These three regulators in particular are fundamental in all stages of biofilm formation; in addition, their pathways overlap, and the significance of their role is strain-dependent. Currently, ribonucleases are also of interest for their potential role as biofilm regulators, and their relationships with QS, c-di-GMP and sRNAs have been investigated. This review article will focus on these four biofilm regulators (ribonucleases, QS, c-di-GMP and sRNAs) and the relationships between them.
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Affiliation(s)
- Manuel Condinho
- Instituto de Tecnologia Química e Biológica António XavierUniversidade Nova de LisboaOeirasPortugal
| | - Beatriz Carvalho
- Instituto de Tecnologia Química e Biológica António XavierUniversidade Nova de LisboaOeirasPortugal
| | - Adriana Cruz
- iBB‐Institute for Bioengineering and Biosciences (IBB)Instituto Superior TécnicoLisboaPortugal
- i4HB‐Institute for Health and BioeconomyInstituto Superior TécnicoLisboaPortugal
| | - Sandra N. Pinto
- iBB‐Institute for Bioengineering and Biosciences (IBB)Instituto Superior TécnicoLisboaPortugal
- i4HB‐Institute for Health and BioeconomyInstituto Superior TécnicoLisboaPortugal
| | - Cecília M. Arraiano
- Instituto de Tecnologia Química e Biológica António XavierUniversidade Nova de LisboaOeirasPortugal
| | - Vânia Pobre
- Instituto de Tecnologia Química e Biológica António XavierUniversidade Nova de LisboaOeirasPortugal
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17
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Cao Z, Liu Z, Mao X. Application of Quorum Sensing in Metabolic Engineering. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2023; 71:5062-5074. [PMID: 36967589 DOI: 10.1021/acs.jafc.3c00176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Metabolic engineering is widely utilized in the food and other fields and has the benefits of low-cost substrates, eco-friendly fermentation processes, and efficient substrate synthesis. Microbial synthesis by metabolic engineering requires maintaining the productive capacity of the microorganism. Moreover, economic reasons limit the use of inducers in the exogenous synthesis pathway. Most unicellular microorganisms can interact by emitting signaling molecules; this mechanism, known as quorum sensing (QS), is an autoinduced system of microorganisms. With the deepening research on QS systems of different microorganisms, its components are widely used to regulate the metabolic synthesis of microorganisms as a dynamic regulatory system. In this Review, we described the typical bacterial QS mechanisms. Then, we summarized various regulatory strategies for QS and their applications to metabolic engineering. Finally, we underlined the potential for QS modularity in future metabolic engineering and suggested stimulating research on fungal QS systems.
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Affiliation(s)
- Zhuoning Cao
- Qingdao Key Laboratory of Food Biotechnology, College of Food Science and Engineering, Ocean University of China, Qingdao 266404, China
- Key Laboratory of Biological Processing of Aquatic Products, China National Light Industry, Qingdao 266404, China
| | - Zhen Liu
- Qingdao Key Laboratory of Food Biotechnology, College of Food Science and Engineering, Ocean University of China, Qingdao 266404, China
- Key Laboratory of Biological Processing of Aquatic Products, China National Light Industry, Qingdao 266404, China
| | - Xiangzhao Mao
- Qingdao Key Laboratory of Food Biotechnology, College of Food Science and Engineering, Ocean University of China, Qingdao 266404, China
- Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China
- Key Laboratory of Biological Processing of Aquatic Products, China National Light Industry, Qingdao 266404, China
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18
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Biofilms and Benign Colonic Diseases. Int J Mol Sci 2022; 23:ijms232214259. [PMID: 36430737 PMCID: PMC9698058 DOI: 10.3390/ijms232214259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 11/06/2022] [Accepted: 11/10/2022] [Indexed: 11/19/2022] Open
Abstract
The colon has a very large surface area that is covered by a dense mucus layer. The biomass in the colon includes 500-1000 bacterial species at concentrations of ~1012 colony-forming units per gram of feces. The intestinal epithelial cells and the commensal bacteria in the colon have a symbiotic relationship that results in nutritional support for the epithelial cells by the bacteria and maintenance of the optimal commensal bacterial population by colonic host defenses. Bacteria can form biofilms in the colon, but the exact frequency is uncertain because routine methods to undertake colonoscopy (i.e., bowel preparation) may dislodge these biofilms. Bacteria in biofilms represent a complex community that includes living and dead bacteria and an extracellular matrix composed of polysaccharides, proteins, DNA, and exogenous debris in the colon. The formation of biofilms occurs in benign colonic diseases, such as inflammatory bowel disease and irritable bowel syndrome. The development of a biofilm might serve as a marker for ongoing colonic inflammation. Alternatively, the development of biofilms could contribute to the pathogenesis of these disorders by providing sanctuaries for pathogenic bacteria and reducing the commensal bacterial population. Therapeutic approaches to patients with benign colonic diseases could include the elimination of biofilms and restoration of normal commensal bacteria populations. However, these studies will be extremely difficult unless investigators can develop noninvasive methods for measuring and identifying biofilms. These methods that might include the measurement of quorum sensing molecules, measurement of bile acids, and identification of bacteria uniquely associated with biofilms in the colon.
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19
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Characterization of MroQ-Dependent Maturation and Export of the Staphylococcus aureus Accessory Gene Regulatory System Autoinducing Peptide. Infect Immun 2022; 90:e0026322. [PMID: 36073934 PMCID: PMC9584314 DOI: 10.1128/iai.00263-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Gram-positive bacteria produce small autoinducing peptides (AIPs), which act to regulate expression of genes that promote adaptive traits, including virulence. The Gram-positive pathogen Staphylococcus aureus generates a cyclic AIP that controls expression of virulence factors via the accessory gene regulatory (Agr) system. S. aureus strains belong to one of four Agr groups (Agr-I, -II, -III, and -IV); each group harbors allelic variants of AgrD, the precursor of AIP. In a prior screen for S. aureus virulence factors, we identified MroQ, a putative peptidase. A ΔmroQ mutant closely resembled a Δagr mutant and had significant defects in AIP production in an Agr-I strain. Here, we show that expression of AgrD-I in a ΔmroQ mutant leads to accumulation of an AIP processing intermediate at the membrane that coincides with a loss of secreted mature AIP, indicating that MroQ promotes maturation of AgrD-I. MroQ is conserved in all Agr sequence variants, suggesting either identical function among all Agr types or activity specific to Agr-I strains. Our data indicate that MroQ is required for AIP maturation and activity in Agr-I, -II, and -IV strains irrespective of background. However, MroQ is not required for Agr-III activity despite an identifiable role in peptide maturation. Isogenic Δagr and Δagr ΔmroQ strains complemented with Agr-I to -IV validated the critical role of MroQ in the generation of active AIP-I, -II, and -IV but not AIP-III. These findings were reinforced by skin infection studies with mice. Our data substantiate the prevailing model that MroQ is a mediator of cyclic peptide maturation.
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20
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Reconstitution of the S. aureus agr quorum sensing pathway reveals a direct role for the integral membrane protease MroQ in pheromone biosynthesis. Proc Natl Acad Sci U S A 2022; 119:e2202661119. [PMID: 35939668 PMCID: PMC9388083 DOI: 10.1073/pnas.2202661119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
In Staphylococcus aureus, virulence is under the control of a quorum sensing (QS) circuit encoded in the accessory gene regulator (agr) genomic locus. Key to this pathogenic behavior is the production and signaling activity of a secreted pheromone, the autoinducing peptide (AIP), generated following the ribosomal synthesis and posttranslational modification of a precursor polypeptide, AgrD, through two discrete cleavage steps. The integral membrane protease AgrB is known to catalyze the first processing event, generating the AIP biosynthetic intermediate, AgrD (1-32) thiolactone. However, the identity of the second protease in this biosynthetic pathway, which removes an N-terminal leader sequence, has remained ambiguous. Here, we show that membrane protease regulator of agr QS (MroQ), an integral membrane protease recently implicated in the agr response, is directly involved in AIP production. Genetic complementation and biochemical experiments reveal that MroQ proteolytic activity is required for AIP biosynthesis in agr specificity group I and group II, but not group III. Notably, as part of this effort, the biosynthesis and AIP-sensing arms of the QS circuit were reconstituted together in vitro. Our experiments also reveal the molecular features guiding MroQ cleavage activity, a critical factor in defining agr specificity group identity. Collectively, our study adds to the molecular understanding of the agr response and Staphylococcus aureus virulence.
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21
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Turner AB, Gerner E, Firdaus R, Echeverz M, Werthén M, Thomsen P, Almqvist S, Trobos M. Role of sodium salicylate in Staphylococcus aureus quorum sensing, virulence, biofilm formation and antimicrobial susceptibility. Front Microbiol 2022; 13:931839. [PMID: 35992652 PMCID: PMC9384861 DOI: 10.3389/fmicb.2022.931839] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Accepted: 07/06/2022] [Indexed: 01/01/2023] Open
Abstract
The widespread threat of antibiotic resistance requires new treatment options. Disrupting bacterial communication, quorum sensing (QS), has the potential to reduce pathogenesis by decreasing bacterial virulence. The aim of this study was to investigate the influence of sodium salicylate (NaSa) on Staphylococcus aureus QS, virulence production and biofilm formation. In S. aureus ATCC 25923 (agr III), with or without serum, NaSa (10 mM) downregulated the agr QS system and decreased the secretion levels of alpha-hemolysin, staphopain A and delta-hemolysin. Inhibition of agr expression caused a downregulation of delta-hemolysin, decreasing biofilm dispersal and increasing biofilm formation on polystyrene and titanium under static conditions. In contrast, NaSa did not increase biofilm biomass under flow but caused one log10 reduction in biofilm viability on polystyrene pegs, resulting in biofilms being twice as susceptible to rifampicin. A concentration-dependent effect of NaSa was further observed, where high concentrations (10 mM) decreased agr expression, while low concentrations (≤0.1 mM) increased agr expression. In S. aureus 8325-4 (agr I), a high concentration of NaSa (10 mM) decreased hla expression, and a low concentration of NaSa (≤1 mM) increased rnaIII and hla expression. The activity of NaSa on biofilm formation was dependent on agr type and material surface. Eight clinical strains isolated from prosthetic joint infection (PJI) or wound infection belonging to each of the four agr types were evaluated. The four PJI S. aureus strains did not change their biofilm phenotype with NaSa on the clinically relevant titanium surface. Half of the wound strains (agr III and IV) did not change the biofilm phenotype in the 3D collagen wound model. In addition, compared to the control, ATCC 25923 biofilms formed with 10 mM NaSa in the collagen model were more susceptible to silver. It is concluded that NaSa can inhibit QS in S. aureus, decreasing the levels of toxin production with certain modulation of biofilm formation. The effect on biofilm formation was dependent on the strain and material surface. It is suggested that the observed NaSa inhibition of bacterial communication is a potential alternative or adjuvant to traditional antibiotics.
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Affiliation(s)
- Adam Benedict Turner
- Department of Biomaterials, University of Gothenburg, The Sahlgrenska Academy, Gothenburg, Sweden
- Center for Antibiotic Resistance Research (CARe), University of Gothenburg, Gothenburg, Sweden
| | - Erik Gerner
- Department of Biomaterials, University of Gothenburg, The Sahlgrenska Academy, Gothenburg, Sweden
- Center for Antibiotic Resistance Research (CARe), University of Gothenburg, Gothenburg, Sweden
- Mölnlycke Health Care AB, Gothenburg, Sweden
| | - Rininta Firdaus
- Department of Biomaterials, University of Gothenburg, The Sahlgrenska Academy, Gothenburg, Sweden
- Center for Antibiotic Resistance Research (CARe), University of Gothenburg, Gothenburg, Sweden
| | - Maite Echeverz
- Microbial Pathogenesis Research Unit, Public University of Navarre, Pamplona, Spain
| | - Maria Werthén
- Department of Biomaterials, University of Gothenburg, The Sahlgrenska Academy, Gothenburg, Sweden
- Center for Antibiotic Resistance Research (CARe), University of Gothenburg, Gothenburg, Sweden
| | - Peter Thomsen
- Department of Biomaterials, University of Gothenburg, The Sahlgrenska Academy, Gothenburg, Sweden
| | | | - Margarita Trobos
- Department of Biomaterials, University of Gothenburg, The Sahlgrenska Academy, Gothenburg, Sweden
- Center for Antibiotic Resistance Research (CARe), University of Gothenburg, Gothenburg, Sweden
- *Correspondence: Margarita Trobos,
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22
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Durand BARN, Pouget C, Magnan C, Molle V, Lavigne JP, Dunyach-Remy C. Bacterial Interactions in the Context of Chronic Wound Biofilm: A Review. Microorganisms 2022; 10:microorganisms10081500. [PMID: 35893558 PMCID: PMC9332326 DOI: 10.3390/microorganisms10081500] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Revised: 07/15/2022] [Accepted: 07/21/2022] [Indexed: 02/04/2023] Open
Abstract
Chronic wounds, defined by their resistance to care after four weeks, are a major concern, affecting millions of patients every year. They can be divided into three types of lesions: diabetic foot ulcers (DFU), pressure ulcers (PU), and venous/arterial ulcers. Once established, the classical treatment for chronic wounds includes tissue debridement at regular intervals to decrease biofilm mass constituted by microorganisms physiologically colonizing the wound. This particular niche hosts a dynamic bacterial population constituting the bed of interaction between the various microorganisms. The temporal reshuffle of biofilm relies on an organized architecture. Microbial community turnover is mainly associated with debridement (allowing transitioning from one major representant to another), but also with microbial competition and/or collaboration within wounds. This complex network of species and interactions has the potential, through diversity in antagonist and/or synergistic crosstalk, to accelerate, delay, or worsen wound healing. Understanding these interactions between microorganisms encountered in this clinical situation is essential to improve the management of chronic wounds.
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Affiliation(s)
- Benjamin A. R. N. Durand
- Bacterial Virulence and Chronic Infections, UMR 1047, Université Montpellier, INSERM, Service de Microbiologie et Hygiène Hospitalière, CHU Nîmes, 30908 Nîmes, France; (B.A.R.N.D.); (C.P.); (C.M.); (J.-P.L.)
| | - Cassandra Pouget
- Bacterial Virulence and Chronic Infections, UMR 1047, Université Montpellier, INSERM, Service de Microbiologie et Hygiène Hospitalière, CHU Nîmes, 30908 Nîmes, France; (B.A.R.N.D.); (C.P.); (C.M.); (J.-P.L.)
| | - Chloé Magnan
- Bacterial Virulence and Chronic Infections, UMR 1047, Université Montpellier, INSERM, Service de Microbiologie et Hygiène Hospitalière, CHU Nîmes, 30908 Nîmes, France; (B.A.R.N.D.); (C.P.); (C.M.); (J.-P.L.)
| | - Virginie Molle
- Laboratory of Pathogen Host Interactions, Université de Montpellier, CNRS, UMR 5235, 34000 Montpellier, France;
| | - Jean-Philippe Lavigne
- Bacterial Virulence and Chronic Infections, UMR 1047, Université Montpellier, INSERM, Service de Microbiologie et Hygiène Hospitalière, CHU Nîmes, 30908 Nîmes, France; (B.A.R.N.D.); (C.P.); (C.M.); (J.-P.L.)
| | - Catherine Dunyach-Remy
- Bacterial Virulence and Chronic Infections, UMR 1047, Université Montpellier, INSERM, Service de Microbiologie et Hygiène Hospitalière, CHU Nîmes, 30908 Nîmes, France; (B.A.R.N.D.); (C.P.); (C.M.); (J.-P.L.)
- Correspondence: ; Tel.: +33-466-683-202
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23
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Martínez OF, Duque HM, Franco OL. Peptidomimetics as Potential Anti-Virulence Drugs Against Resistant Bacterial Pathogens. Front Microbiol 2022; 13:831037. [PMID: 35516442 PMCID: PMC9062693 DOI: 10.3389/fmicb.2022.831037] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Accepted: 02/28/2022] [Indexed: 12/11/2022] Open
Abstract
The uncontrollable spread of superbugs calls for new approaches in dealing with microbial-antibiotic resistance. Accordingly, the anti-virulence approach has arisen as an attractive unconventional strategy to face multidrug-resistant pathogens. As an emergent strategy, there is an imperative demand for discovery, design, and development of anti-virulence drugs. In this regard, peptidomimetic compounds could be a valuable source of anti-virulence drugs, since these molecules circumvent several shortcomings of natural peptide-based drugs like proteolytic instability, immunogenicity, toxicity, and low bioavailability. Some emerging evidence points to the feasibility of peptidomimetics to impair pathogen virulence. Consequently, in this review, we shed some light on the potential of peptidomimetics as anti-virulence drugs to overcome antibiotic resistance. Specifically, we address the anti-virulence activity of peptidomimetics against pathogens' secretion systems, biofilms, and quorum-sensing systems.
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Affiliation(s)
- Osmel Fleitas Martínez
- Programa de Pós-Graduação em Ciências Genômicas e Biotecnologia, Centro de Análises Proteômicas e Bioquímicas, Universidade Católica de Brasília, Brasília, Brazil.,Programa de Pós-Graduação em Biotecnologia, S-Inova Biotech, Universidade Católica Dom Bosco, Campo Grande, Brazil
| | - Harry Morales Duque
- Programa de Pós-Graduação em Ciências Genômicas e Biotecnologia, Centro de Análises Proteômicas e Bioquímicas, Universidade Católica de Brasília, Brasília, Brazil
| | - Octávio Luiz Franco
- Programa de Pós-Graduação em Ciências Genômicas e Biotecnologia, Centro de Análises Proteômicas e Bioquímicas, Universidade Católica de Brasília, Brasília, Brazil.,Programa de Pós-Graduação em Biotecnologia, S-Inova Biotech, Universidade Católica Dom Bosco, Campo Grande, Brazil
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24
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Ferraro NJ, Pires MM. Genetic Determinants of Surface Accessibility in Staphylococcus aureus. Bioconjug Chem 2022; 33:767-772. [PMID: 35499914 DOI: 10.1021/acs.bioconjchem.2c00173] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Bacterial cell walls represent one of the most prominent targets of antibacterial agents. These agents include natural products (e.g., vancomycin) and proteins stemming from the innate immune system (e.g., peptidoglycan-recognition proteins and lysostaphin). Among bacterial pathogens that infect humans, Staphylococcus aureus (S. aureus) continues to impose a tremendous healthcare burden across the globe. S. aureus has evolved countermeasures that can directly restrict the accessibility of innate immune proteins, effectively protecting itself from threats that target key cell well components. We recently described a novel assay that directly reports on the accessibility of molecules to the peptidoglycan layer within the bacterial cell wall of S. aureus. The assay relies on site-specific chemical remodeling of the peptidoglycan with a biorthogonal handle. Here, we disclose the application of our assay to a screen of a nonredundant transposon mutant library for susceptibility of the peptidoglycan layer with the goal of identifying genes that contribute to the control of cell surface accessibility. We discovered several genes that resulted in higher accessibility levels to the peptidoglycan layer and showed that these genes modulate sensitivity to lysostaphin. These results indicate that this assay platform can be leveraged to gain further insight into the biology of bacterial cell surfaces.
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Affiliation(s)
- Noel J Ferraro
- Department of Chemistry University of Virginia Charlottesville, Virginia 22904, United States
| | - Marcos M Pires
- Department of Chemistry University of Virginia Charlottesville, Virginia 22904, United States
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25
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Ogura K, Furuya H, Takahashi N, Shibata K, Endo M, Watanabe S, Cui L, Miyoshi-Akiyama T, Okamoto S, Ogai K, Sugama J. Interspecies Regulation Between Staphylococcus caprae and Staphylococcus aureus Colonized on Healed Skin After Injury. Front Microbiol 2022; 13:818398. [PMID: 35300478 PMCID: PMC8921658 DOI: 10.3389/fmicb.2022.818398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Accepted: 01/20/2022] [Indexed: 12/04/2022] Open
Abstract
Staphylococcus spp. colonize commensally on the human skin. Some commensal coagulase-negative staphylococci and Staphylococcus aureus are also involved in nosocomial infections. Bacteria were collected from skin healed from pressure injury (PI). After the collection time points, some patients suffered from recurrent PI (RPI). This study analyzed the characteristics of Staphylococcus spp. on healed skin before recurrence between healed skin that suffered from RPI within 6 weeks (RPI group) and healed skin that did not suffer within the duration (non-RPI group) by Staphylococcus spp.-specific sequencing. Of the seven patients in the RPI group, two were dominated by S. aureus and four by Staphylococcus caprae, coagulase-negative human commensal staphylococci in the RPI group. Using mouse models, both S. caprae and S. aureus, but not Staphylococcus epidermidis, colonized on skin healed from injury at significantly higher rates than normal skin. Although subcutaneous injection of S. caprae did not induce lesion formation, the bacterium exhibited high hemolytic activity on human red blood cells. Lesion formation by subcutaneous injection of S. aureus was significantly suppressed in the presence of S. caprae. The hemolytic activity of rabbit blood cells of S. aureus was suppressed by S. caprae, whereas the hemolytic activity of S. caprae was dramatically suppressed by S. aureus. Data indicated that each of the two Staphylococcus spp. suppresses the pathogenicity of the other and that the imbalance between the two is associated with RPI.
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Affiliation(s)
- Kohei Ogura
- Advanced Health Care Science Research Unit, Institute for Frontier Science Initiative, Kanazawa University, Kanazawa, Japan
| | - Hiroka Furuya
- Department of Clinical Laboratory Science, Faculty of Health Sciences, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Japan
| | - Natsuki Takahashi
- Advanced Health Care Science Research Unit, Institute for Frontier Science Initiative, Kanazawa University, Kanazawa, Japan
| | - Kana Shibata
- Advanced Health Care Science Research Unit, Institute for Frontier Science Initiative, Kanazawa University, Kanazawa, Japan
| | - Maho Endo
- Advanced Health Care Science Research Unit, Institute for Frontier Science Initiative, Kanazawa University, Kanazawa, Japan
| | - Shinya Watanabe
- Division of Bacteriology, Department of Infection and Immunity, Faculty of Medicine, Jichi Medical University, Shimotsuke, Japan
| | - Longzhu Cui
- Division of Bacteriology, Department of Infection and Immunity, Faculty of Medicine, Jichi Medical University, Shimotsuke, Japan
| | - Tohru Miyoshi-Akiyama
- Pathogenic Microbe Laboratory, Research Institute, National Center for Global Health and Medicine, Shinjuku, Japan
| | - Shigefumi Okamoto
- Advanced Health Care Science Research Unit, Institute for Frontier Science Initiative, Kanazawa University, Kanazawa, Japan.,Department of Clinical Laboratory Science, Faculty of Health Sciences, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Japan
| | - Kazuhiro Ogai
- AI Hospital/Macro Signal Dynamics Research and Development Center, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Japan
| | - Junko Sugama
- Advanced Health Care Science Research Unit, Institute for Frontier Science Initiative, Kanazawa University, Kanazawa, Japan.,Research Center for Implementation Nursing Science Initiative, School of Health Sciences, Fujita Health University, Toyoake, Japan
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26
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To HTA, Chhetri V, Settachaimongkon S, Prakitchaiwattana C. Stress tolerance-Bacillus with a wide spectrum bacteriocin as an alternative approach for food bio-protective culture production. Food Control 2022. [DOI: 10.1016/j.foodcont.2021.108598] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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27
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Tan L, Huang Y, Shang W, Yang Y, Peng H, Hu Z, Wang Y, Rao Y, Hu Q, Rao X, Hu X, Li M, Chen K, Li S. Accessory Gene Regulator (agr) Allelic Variants in Cognate Staphylococcus aureus Strain Display Similar Phenotypes. Front Microbiol 2022; 13:700894. [PMID: 35295312 PMCID: PMC8919982 DOI: 10.3389/fmicb.2022.700894] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Accepted: 01/14/2022] [Indexed: 11/13/2022] Open
Abstract
The accessory gene regulator (agr) quorum-sensing system is an important global regulatory system of Staphylococcus aureus and contributes to its pathogenicity. The S. aureus agr system is divided into four agr groups based on the amino acid polymorphisms of AgrB, AgrD, and AgrC. The agr activation is group-specific, resulting in variations in agr activity and pathogenicity among the four agr groups. Strains with divergent agr system always have different phenotypes. In the present report, we, respectively, exchanged the agr system of a certain S. aureus with other three agr alleles and assessed the corresponding phenotypes of these congenic strains. Replacement of the agr system led to significant variations in hemolytic activity, protein expression, and virulence gene expression comparing with that of the parental strain. Interestingly, we found that the biological characteristics of these agr congenic strains in the same strain background were highly similar to each other, and the allele-dependent differences of the agr systems were weakened. These findings indicate that the allele-dependent agr predilections of S. aureus are determined by some factors in addition to the polymorphisms of AgrB, AgrD, and AgrC. Future studies may reveal the novel mechanism to improve our understanding of the agr network.
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Affiliation(s)
- Li Tan
- College of Basic Medical Sciences, Army Medical University, Chongqing, China
| | - Yuyang Huang
- Queen Mary College, Nanchang University, Nanchang, China
| | - Weilong Shang
- College of Basic Medical Sciences, Army Medical University, Chongqing, China
| | - Yi Yang
- College of Basic Medical Sciences, Army Medical University, Chongqing, China
| | - Huagang Peng
- College of Basic Medical Sciences, Army Medical University, Chongqing, China
| | - Zhen Hu
- College of Basic Medical Sciences, Army Medical University, Chongqing, China
| | - Yuting Wang
- College of Basic Medical Sciences, Army Medical University, Chongqing, China
| | - Yifan Rao
- College of Basic Medical Sciences, Army Medical University, Chongqing, China
| | - Qiwen Hu
- College of Basic Medical Sciences, Army Medical University, Chongqing, China
| | - Xiancai Rao
- College of Basic Medical Sciences, Army Medical University, Chongqing, China
| | - Xiaomei Hu
- College of Basic Medical Sciences, Army Medical University, Chongqing, China
| | - Ming Li
- College of Basic Medical Sciences, Army Medical University, Chongqing, China
| | - Kaisen Chen
- The First Affiliated Hospital of Nanchang University, Nanchang, China
- *Correspondence: Kaisen Chen,
| | - Shu Li
- College of Basic Medical Sciences, Army Medical University, Chongqing, China
- Shu Li,
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28
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Raghuram V, Alexander AM, Loo HQ, Petit RA, Goldberg JB, Read TD. Species-Wide Phylogenomics of the Staphylococcus aureus Agr Operon Revealed Convergent Evolution of Frameshift Mutations. Microbiol Spectr 2022; 10:e0133421. [PMID: 35044202 PMCID: PMC8768832 DOI: 10.1128/spectrum.01334-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Accepted: 01/03/2022] [Indexed: 11/20/2022] Open
Abstract
Staphylococcus aureus is a prominent nosocomial pathogen that causes several life-threatening diseases, such as pneumonia and bacteremia. S. aureus modulates the expression of its arsenal of virulence factors through sensing and integrating responses to environmental signals. The agr (accessory gene regulator) quorum sensing (QS) system is a major regulator of virulence phenotypes in S. aureus. There are four agr specificity groups each with a different autoinducer peptide sequence encoded by the agrD gene. Although agr is critical for the expression of many toxins, paradoxically, S. aureus strains often have nonfunctional agr activity due to loss-of-function mutations in the four-gene agr operon. To understand patterns in agr variability across S. aureus, we undertook a species-wide genomic investigation. We developed a software tool (AgrVATE; https://github.com/VishnuRaghuram94/AgrVATE) for typing and detecting frameshift mutations in the agr operon. In an analysis of over 40,000 S. aureus genomes, we showed a close association between agr type and S. aureus clonal complex. We also found a strong linkage between agrBDC alleles (encoding the peptidase, autoinducing peptide itself, and peptide sensor, respectively) but not agrA (encoding the response regulator). More than 5% of the genomes were found to have frameshift mutations in the agr operon. While 52% of these frameshifts occurred only once in the entire species, we observed cases where the recurring mutations evolved convergently across different clonal lineages with no evidence of long-term phylogenetic transmission, suggesting that strains with agr frameshifts were evolutionarily short-lived. Overall, genomic analysis of agr operon suggests evolution through multiple processes with functional consequences that are not fully understood. IMPORTANCE Staphylococcus aureus is a globally pervasive pathogen that produces a plethora of toxic molecules that can harm host immune cells. Production of these toxins is mainly controlled by an active agr quorum-sensing system, which senses and responds to bacterial cell density. However, there are many reports of S. aureus strains with genetic changes leading to impaired agr activity that are often found during chronic bloodstream infections and may be associated with increased disease severity. We developed an open-source software called AgrVATE to type agr systems and identify mutations. We used AgrVATE for a species-wide genomic survey of S. aureus, finding that more than 5% of strains in the public database had nonfunctional agr systems. We also provided new insights into the evolution of these genetic mutations in the agr system. Overall, this study contributes to our understanding of a common but relatively understudied means of virulence regulation in S. aureus.
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Affiliation(s)
- Vishnu Raghuram
- Microbiology and Molecular Genetics Program, Graduate Division of Biological and Biomedical Sciences, Laney Graduate School, Emory University, Atlanta, Georgia, USA
| | - Ashley M. Alexander
- Population Biology, Ecology, and Evolution Program, Graduate Division of Biological and Biomedical Sciences, Laney Graduate School, Emory University, Atlanta, Georgia, USA
| | - Hui Qi Loo
- Department of Biology, Emory University, Atlanta, Georgia, USA
| | - Robert A. Petit
- Division of Infectious Diseases, Department of Medicine, Emory University, Atlanta, Georgia, USA
| | - Joanna B. Goldberg
- Division of Pulmonary, Allergy and Immunology, Cystic Fibrosis, and Sleep, Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Timothy D. Read
- Division of Infectious Diseases, Department of Medicine, Emory University, Atlanta, Georgia, USA
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29
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Aubourg M, Pottier M, Léon A, Bernay B, Dhalluin A, Cacaci M, Torelli R, Ledormand P, Martini C, Sanguinetti M, Auzou M, Gravey F, Giard JC. Inactivation of the Response Regulator AgrA Has a Pleiotropic Effect on Biofilm Formation, Pathogenesis and Stress Response in Staphylococcus lugdunensis. Microbiol Spectr 2022; 10:e0159821. [PMID: 35138170 PMCID: PMC8826819 DOI: 10.1128/spectrum.01598-21] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Accepted: 01/07/2022] [Indexed: 12/24/2022] Open
Abstract
Staphylococcus lugdunensis is a coagulase-negative Staphylococcus that emerges as an important opportunistic pathogen. However, little is known about the regulation underlying the transition from commensal to virulent state. Based on knowledge of S. aureus virulence, we suspected that the agr quorum sensing system may be an important determinant for the pathogenicity of S. lugdunensis. We investigated the functions of the transcriptional regulator AgrA using the agrA deletion mutant. AgrA played a role in cell pigmentation: ΔargA mutant colonies were white while the parental strains were slightly yellow. Compared with the wild-type strain, the ΔargA mutant was affected in its ability to form biofilm and was less able to survive in mice macrophages. Moreover, the growth of ΔagrA was significantly reduced by the addition of 10% NaCl or 0.4 mM H2O2 and its survival after 2 h in the presence of 1 mM H2O2 was more than 10-fold reduced. To explore the mechanisms involved beyond these phenotypes, the ΔagrA proteome and transcriptome were characterized by mass spectrometry and RNA-Seq. We found that AgrA controlled several virulence factors as well as stress-response factors, which are well correlated with the reduced resistance of the ΔagrA mutant to osmotic and oxidative stresses. These results were not the consequence of the deregulation of RNAIII of the agr system, since no phenotype or alteration of the proteomic profile has been observed for the ΔRNAIII mutant. Altogether, our results highlighted that the AgrA regulator of S. lugdunensis played a key role in its ability to become pathogenic. IMPORTANCE Although belonging to the natural human skin flora, Staphylococcus lugdunensis is recognized as a particularly aggressive and destructive pathogen. This study aimed to characterize the role of the response regulator AgrA, which is a component of the quorum-sensing agr system and known to be a major element in the regulation of pathogenicity and biofilm formation in Staphylococcus aureus. In the present study, we showed that, contrary to S. aureus, the agrA deletion mutant produced less biofilm. Inactivation of agrA conferred a white colony phenotype and impacted S. lugdunensis in its ability to survive in mice macrophages and to cope with osmotic and oxidative stresses. By global proteomic and transcriptomic approaches, we identified the AgrA regulon, bringing molecular bases underlying the observed phenotypes. Together, our data showed the importance of AgrA in the opportunistic pathogenic behavior of S. lugdunensis allowing it to be considered as an interesting therapeutic target.
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Affiliation(s)
- Marion Aubourg
- Université de Caen Normandie, Dynamicure, INSERM U1311, CHU de Caen, Caen, France
| | - Marine Pottier
- Université de Caen Normandie, Dynamicure, INSERM U1311, CHU de Caen, Caen, France
- LABÉO Frank Duncombe, Caen, France
| | - Albertine Léon
- Université de Caen Normandie, Dynamicure, INSERM U1311, CHU de Caen, Caen, France
- LABÉO Frank Duncombe, Caen, France
| | - Benoit Bernay
- Plateforme Proteogen SFR ICORE 4206, Université de Caen Normandie, Caen, France
| | - Anne Dhalluin
- Université de Caen Normandie, Dynamicure, INSERM U1311, CHU de Caen, Caen, France
| | - Margherita Cacaci
- Institute of Microbiology, Catholic University of Sacred Heart, L. go F. Vito 1, Rome, Italy
| | - Riccardo Torelli
- Institute of Microbiology, Catholic University of Sacred Heart, L. go F. Vito 1, Rome, Italy
| | | | - Cecilia Martini
- Institute of Microbiology, Catholic University of Sacred Heart, L. go F. Vito 1, Rome, Italy
| | - Maurizio Sanguinetti
- Institute of Microbiology, Catholic University of Sacred Heart, L. go F. Vito 1, Rome, Italy
| | - Michel Auzou
- CHU de Caen, Laboratoire de Microbiologie, Caen, France
| | - François Gravey
- Université de Caen Normandie, Dynamicure, INSERM U1311, CHU de Caen, Caen, France
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Coquant G, Aguanno D, Pham S, Grellier N, Thenet S, Carrière V, Grill JP, Seksik P. Gossip in the gut: Quorum sensing, a new player in the host-microbiota interactions. World J Gastroenterol 2021; 27:7247-7270. [PMID: 34876787 PMCID: PMC8611211 DOI: 10.3748/wjg.v27.i42.7247] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 08/17/2021] [Accepted: 10/27/2021] [Indexed: 02/06/2023] Open
Abstract
Bacteria are known to communicate with each other and regulate their activities in social networks by secreting and sensing signaling molecules called autoinducers, a process known as quorum sensing (QS). This is a growing area of research in which we are expanding our understanding of how bacteria collectively modify their behavior but are also involved in the crosstalk between the host and gut microbiome. This is particularly relevant in the case of pathologies associated with dysbiosis or disorders of the intestinal ecosystem. This review will examine the different QS systems and the evidence for their presence in the intestinal ecosystem. We will also provide clues on the role of QS molecules that may exert, directly or indirectly through their bacterial gossip, an influence on intestinal epithelial barrier function, intestinal inflammation, and intestinal carcinogenesis. This review aims to provide evidence on the role of QS molecules in gut physiology and the potential shared by this new player. Better understanding the impact of intestinal bacterial social networks and ultimately developing new therapeutic strategies to control intestinal disorders remains a challenge that needs to be addressed in the future.
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Affiliation(s)
- Garance Coquant
- Centre de Recherche Saint-Antoine, INSERM, Sorbonne Université, Paris 75012, France
| | - Doriane Aguanno
- Centre de Recherche Saint-Antoine, INSERM, Sorbonne Université, Paris 75012, France
- EPHE, PSL University, Paris 75014, France
| | - Sandrine Pham
- Centre de Recherche Saint-Antoine, INSERM, Sorbonne Université, Paris 75012, France
- EPHE, PSL University, Paris 75014, France
| | - Nathan Grellier
- Centre de Recherche Saint-Antoine, INSERM, Sorbonne Université, Paris 75012, France
| | - Sophie Thenet
- Centre de Recherche Saint-Antoine, INSERM, Sorbonne Université, Paris 75012, France
- EPHE, PSL University, Paris 75014, France
| | - Véronique Carrière
- Centre de Recherche Saint-Antoine, INSERM, Sorbonne Université, Paris 75012, France
| | - Jean-Pierre Grill
- Centre de Recherche Saint-Antoine, INSERM, Sorbonne Université, Paris 75012, France
| | - Philippe Seksik
- Centre de Recherche Saint-Antoine, INSERM, Sorbonne Université, Paris 75012, France
- Department of Gastroenterology and Nutrition, Saint-Antoine Hospital, APHP, Paris 75012, France
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Iobbi V, Brun P, Bernabé G, Dougué Kentsop RA, Donadio G, Ruffoni B, Fossa P, Bisio A, De Tommasi N. Labdane Diterpenoids from Salvia tingitana Etl. Synergize with Clindamycin against Methicillin-Resistant Staphylococcus aureus. Molecules 2021; 26:6681. [PMID: 34771089 PMCID: PMC8587691 DOI: 10.3390/molecules26216681] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 10/29/2021] [Accepted: 11/01/2021] [Indexed: 01/21/2023] Open
Abstract
Quorum-sensing (QS) is a regulatory mechanism in bacterial communication, important for pathogenesis control. The search for small molecules active as quorum-sensing inhibitors (QSI) that can synergize with antibiotics is considered a good strategy to counteract the problem of antibiotic resistance. Here the antimicrobial labdane diterpenoids sclareol (1) and manool (2) extracted from Salvia tingitana were considered as potential QSI against methicillin-resistant Staphylococcus aureus. Only sclareol showed synergistic activity with clindamycin. The quantification of these compounds by LC-MS analysis in the organs and in the calli of S. tingitana showed that sclareol is most abundant in the flower spikes and is produced by calli, while manool is the major labdane of the roots, and is abundant also in the leaves. Other metabolites of the roots were abietane diterpenoids, common in Salvia species, and pentacyclic triterpenoids, bearing a γ-lactone moiety, previously undescribed in Salvia. Docking simulations suggested that 1 and 2 bind to key residues, involved in direct interactions with DNA. They may prevent accessory gene regulator A (AgrA) binding to DNA or AgrA activation upon phosphorylation, to suppress virulence factor expression. The antimicrobial activity of these two compounds probably achieves preventing upregulation of the accessory gene regulator (agr)-regulated genes.
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Affiliation(s)
- Valeria Iobbi
- Department of Pharmacy, University of Genova, Viale Cembrano 4, 16148 Genova, Italy; (V.I.); (R.A.D.K.); (P.F.)
| | - Paola Brun
- Department of Molecular Medicine, University of Padova, Via Gabelli 63, 35121 Padova, Italy; (P.B.); (G.B.)
| | - Giulia Bernabé
- Department of Molecular Medicine, University of Padova, Via Gabelli 63, 35121 Padova, Italy; (P.B.); (G.B.)
| | - Roméo Arago Dougué Kentsop
- Department of Pharmacy, University of Genova, Viale Cembrano 4, 16148 Genova, Italy; (V.I.); (R.A.D.K.); (P.F.)
- Consiglio per la Ricerca e la Sperimentazione in Agricoltura–CREA Centro di ricerca Orticoltura e Florovivaismo, 18038 San Remo, Italy;
| | - Giuliana Donadio
- Department of Pharmacy, University of Salerno, Via Giovanni Paolo II 132, 84084 Salerno, Italy; (G.D.); (N.D.T.)
| | - Barbara Ruffoni
- Consiglio per la Ricerca e la Sperimentazione in Agricoltura–CREA Centro di ricerca Orticoltura e Florovivaismo, 18038 San Remo, Italy;
| | - Paola Fossa
- Department of Pharmacy, University of Genova, Viale Cembrano 4, 16148 Genova, Italy; (V.I.); (R.A.D.K.); (P.F.)
| | - Angela Bisio
- Department of Pharmacy, University of Genova, Viale Cembrano 4, 16148 Genova, Italy; (V.I.); (R.A.D.K.); (P.F.)
| | - Nunziatina De Tommasi
- Department of Pharmacy, University of Salerno, Via Giovanni Paolo II 132, 84084 Salerno, Italy; (G.D.); (N.D.T.)
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Mishra B, Khader R, Felix LO, Frate M, Mylonakis E, Meschwitz S, Fuchs BB. A Substituted Diphenyl Amide Based Novel Scaffold Inhibits Staphylococcus aureus Virulence in a Galleria mellonella Infection Model. Front Microbiol 2021; 12:723133. [PMID: 34675898 PMCID: PMC8524085 DOI: 10.3389/fmicb.2021.723133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Accepted: 09/14/2021] [Indexed: 11/23/2022] Open
Abstract
Antimicrobial compounds can combat microbes through modulating host immune defense, inhibiting bacteria survival and growth, or through impeding or inhibiting virulence factors. In the present study, a panel of substituted diphenyl amide compounds previously found to disrupt bacterial quorum sensing were investigated and several were found to promote survival in the Galleria mellonella model when provided therapeutically to treat a Gram-positive bacterial infection from methicillin-resistant Staphylococcus aureus strain MW2. Out of 21 tested compounds, N-4-Methoxyphenyl-3-(4-methoxyphenyl)-propanamide (AMI 82B) was the most potent at disrupting S. aureus virulence and promoted 50% larvae survival at 120 and 96 h when delivered at 0.5 and 5 mg/Kg, respectively, compared to untreated controls (p < 0.0001). AMI 82B did not exhibit G. mellonella toxicity (LC50 > 144 h) at a delivery concentration up to 5 mg/Kg. Further assessment with mammalian cells suggest AMI 82B hemolytic effects against erythrocytes has an HL50 greater than the highest tested concentration of 64 μg/mL. Against HepG2 hepatic cells, AMI 82B demonstrated an LD50 greater than 64 μg/mL. AMI 82B lacked direct bacteria inhibition with a minimal inhibitory concentration that exceeds 64 μg/mL and no significant reduction in S. aureus growth curve at the same concentration. Assessment via qPCR revealed that AMI 82B significantly depressed quorum sensing genes agr, spa, and icaA (p < 0.05). Thus, AMI 82B therapeutic effect against S. aureus in the G. mellonella infection model is likely an influence on bacterial quorum sensing driven virulence factors and provides an interesting hit compound for this medically important pathogen.
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Affiliation(s)
- Biswajit Mishra
- Division of Infectious Diseases, Rhode Island Hospital, Alpert Medical School of Brown University, Providence, RI, United States
| | - Rajamohammed Khader
- Division of Infectious Diseases, Rhode Island Hospital, Alpert Medical School of Brown University, Providence, RI, United States
| | - Lewis Oscar Felix
- Division of Infectious Diseases, Rhode Island Hospital, Alpert Medical School of Brown University, Providence, RI, United States
| | - Marissa Frate
- Department of Chemistry, Salve Regina University, Newport, RI, United States
| | - Eleftherios Mylonakis
- Division of Infectious Diseases, Rhode Island Hospital, Alpert Medical School of Brown University, Providence, RI, United States
| | - Susan Meschwitz
- Department of Chemistry, Salve Regina University, Newport, RI, United States
| | - Beth Burgwyn Fuchs
- Division of Infectious Diseases, Rhode Island Hospital, Alpert Medical School of Brown University, Providence, RI, United States
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Martins Antunes de Melo WDC, Celiešiūtė-Germanienė R, Šimonis P, Stirkė A. Antimicrobial photodynamic therapy (aPDT) for biofilm treatments. Possible synergy between aPDT and pulsed electric fields. Virulence 2021; 12:2247-2272. [PMID: 34496717 PMCID: PMC8437467 DOI: 10.1080/21505594.2021.1960105] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Currently, microbial biofilms have been the cause of a wide variety of infections in the human body, reaching 80% of all bacterial and fungal infections. The biofilms present specific properties that increase the resistance to antimicrobial treatments. Thus, the development of new approaches is urgent, and antimicrobial photodynamic therapy (aPDT) has been shown as a promising candidate. aPDT involves a synergic association of a photosensitizer (PS), molecular oxygen and visible light, producing highly reactive oxygen species (ROS) that cause the oxidation of several cellular components. This therapy attacks many components of the biofilm, including proteins, lipids, and nucleic acids present within the biofilm matrix; causing inhibition even in the cells that are inside the extracellular polymeric substance (EPS). Recent advances in designing new PSs to increase the production of ROS and the combination of aPDT with other therapies, especially pulsed electric fields (PEF), have contributed to enhanced biofilm inhibition. The PEF has proven to have antimicrobial effect once it is known that extensive chemical reactions occur when electric fields are applied. This type of treatment kills microorganisms not only due to membrane rupture but also due to the formation of reactive compounds including free oxygen, hydrogen, hydroxyl and hydroperoxyl radicals. So, this review aims to show the progress of aPDT and PEF against the biofilms, suggesting that the association of both methods can potentiate their effects and overcome biofilm infections.
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Affiliation(s)
- Wanessa de Cassia Martins Antunes de Melo
- Department of Functional Materials and Electronics, Laboratory of Bioelectric, State Research Institute, Department of Functional Materials and Electronics, Center for Physical Sciences and Technology, Vilnius, Lithuania
| | - Raimonda Celiešiūtė-Germanienė
- Department of Functional Materials and Electronics, Laboratory of Bioelectric, State Research Institute, Department of Functional Materials and Electronics, Center for Physical Sciences and Technology, Vilnius, Lithuania
| | - Povilas Šimonis
- Department of Functional Materials and Electronics, Laboratory of Bioelectric, State Research Institute, Department of Functional Materials and Electronics, Center for Physical Sciences and Technology, Vilnius, Lithuania
| | - Arūnas Stirkė
- Department of Functional Materials and Electronics, Laboratory of Bioelectric, State Research Institute, Department of Functional Materials and Electronics, Center for Physical Sciences and Technology, Vilnius, Lithuania
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Pant N, Eisen DP. Non-Antimicrobial Adjuvant Strategies to Tackle Biofilm-Related Staphylococcus aureus Prosthetic Joint Infections. Antibiotics (Basel) 2021; 10:antibiotics10091060. [PMID: 34572641 PMCID: PMC8465242 DOI: 10.3390/antibiotics10091060] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 08/27/2021] [Accepted: 08/28/2021] [Indexed: 12/15/2022] Open
Abstract
Staphylococcus aureus frequently causes community- and hospital-acquired infections. S. aureus attachment followed by biofilm formation on tissues and medical devices plays a significant role in the establishment of chronic infections. Staphylococcal biofilms encase bacteria in a matrix and protect the cells from antimicrobials and the immune system, resulting in infections that are highly resistant to treatment. The biology of biofilms is complex and varies between organisms. In this review, we focus our discussion on S. aureus biofilms and describe the stages of their formation. We particularly emphasize genetic and biochemical processes that may be vulnerable to novel treatment approaches. Against this background, we discuss treatment strategies that have been successful in animal models of S. aureus biofilm-related infection and consider their possible use for the prevention and eradication of biofilm-related S. aureus prosthetic joint infection.
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Joshi JR, Khazanov N, Charkowski A, Faigenboim A, Senderowitz H, Yedidia I. Interkingdom Signaling Interference: The Effect of Plant-Derived Small Molecules on Quorum Sensing in Plant-Pathogenic Bacteria. ANNUAL REVIEW OF PHYTOPATHOLOGY 2021; 59:153-190. [PMID: 33951403 DOI: 10.1146/annurev-phyto-020620-095740] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
In the battle between bacteria and plants, bacteria often use a population density-dependent regulatory system known as quorum sensing (QS) to coordinate virulence gene expression. In response, plants use innate and induced defense mechanisms that include low-molecular-weight compounds, some of which serve as antivirulence agents by interfering with the QS machinery. The best-characterized QS system is driven by the autoinducer N-acyl-homoserine lactone (AHL), which is produced by AHL synthases (LuxI homologs) and perceived by response regulators (LuxR homologs). Several plant compounds have been shown to directly inhibit LuxI or LuxR. Gaining atomic-level insight into their mode of action and how they interfere with QS enzymes supports the identification and design of novel QS inhibitors.Such information can be gained by combining experimental work with molecular modeling and docking simulations. The summary of these findings shows that plant-derived compounds act as interkingdom cues and that these allomones specifically target bacterial communication systems.
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Affiliation(s)
- Janak Raj Joshi
- Department of Plant Sciences, Agricultural Research Organization, The Volcani Center, Rishon Lezion, Israel 7528809;
- Department of Horticulture and Landscape Architecture, Colorado State University, Fort Collins, Colorado 80523, USA
| | - Netaly Khazanov
- Department of Chemistry, Bar-Ilan University, Ramat-Gan, Israel 5290002;
| | - Amy Charkowski
- Department of Agricultural Biology, Colorado State University, Fort Collins, Colorado 80523, USA
| | - Adi Faigenboim
- Department of Plant Sciences, Agricultural Research Organization, The Volcani Center, Rishon Lezion, Israel 7528809;
| | - Hanoch Senderowitz
- Department of Chemistry, Bar-Ilan University, Ramat-Gan, Israel 5290002;
| | - Iris Yedidia
- Department of Plant Sciences, Agricultural Research Organization, The Volcani Center, Rishon Lezion, Israel 7528809;
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36
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Torres Salazar BO, Heilbronner S, Peschel A, Krismer B. Secondary Metabolites Governing Microbiome Interaction of Staphylococcal Pathogens and Commensals. Microb Physiol 2021; 31:198-216. [PMID: 34325424 DOI: 10.1159/000517082] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Accepted: 05/03/2021] [Indexed: 11/19/2022]
Abstract
Various Staphylococcus species colonize skin and upper airways of warm-blooded animals. They compete successfully with many other microorganisms under the hostile and nutrient-poor conditions of these habitats using mechanisms that we are only beginning to appreciate. Small-molecule mediators, whose biosynthesis requires complex enzymatic cascades, so-called secondary metabolites, have emerged as crucial components of staphylococcal microbiome interactions. Such mediators belong to a large variety of compound classes and several of them have attractive properties for future drug development. They include, for instance, bacteriocins such as lanthipeptides, thiopeptides, and fibupeptides that inhibit bacterial competitor species; signaling molecules such as thiolactone peptides that induce or inhibit sensory cascades in other bacteria; or metallophores such as staphyloferrins and staphylopine that scavenge scant transition metal ions. For some secondary metabolites such as the aureusimines, the exact function remains to be elucidated. How secondary metabolites shape the fitness of Staphylococcus species in the complex context of other microbial and host defense factors remains a challenging field of future research. A detailed understanding will help to harness staphylococcal secondary metabolites for excluding the pathogenic species Staphylococcus aureus from the nasal microbiomes of at-risk patients, and it will be instrumental for the development of advanced anti-infective interventions.
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Affiliation(s)
- Benjamin O Torres Salazar
- Department of Infection Biology, Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Tübingen, Germany.,Cluster of Excellence EXC 2124 Controlling Microbes to Fight Infections, Tübingen, Germany.,German Center for Infection Research (DZIF), partner site Tübingen, Tübingen, Germany
| | - Simon Heilbronner
- Department of Infection Biology, Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Tübingen, Germany.,Cluster of Excellence EXC 2124 Controlling Microbes to Fight Infections, Tübingen, Germany.,German Center for Infection Research (DZIF), partner site Tübingen, Tübingen, Germany
| | - Andreas Peschel
- Department of Infection Biology, Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Tübingen, Germany.,Cluster of Excellence EXC 2124 Controlling Microbes to Fight Infections, Tübingen, Germany.,German Center for Infection Research (DZIF), partner site Tübingen, Tübingen, Germany
| | - Bernhard Krismer
- Department of Infection Biology, Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Tübingen, Germany.,Cluster of Excellence EXC 2124 Controlling Microbes to Fight Infections, Tübingen, Germany.,German Center for Infection Research (DZIF), partner site Tübingen, Tübingen, Germany
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Liu H, Shi F, Tan S, Yu X, Lai W, Li Y. Engineering a Bifunctional ComQXPA-P srfA Quorum-Sensing Circuit for Dynamic Control of Gene Expression in Corynebacterium glutamicum. ACS Synth Biol 2021; 10:1761-1774. [PMID: 34165971 DOI: 10.1021/acssynbio.1c00149] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Corynebacterium glutamicum is an important industrial workhorse for the production of amino acids and other chemicals. However, the engineering of C. glutamicum is inflexible due to the lack of dynamic regulation tools. In this study, a quorum sensing (QS) circuit and its modulated hfq-sRNA cassette were constructed, and the dynamic control of gene expression by these bifunctional circuits was researched. First, the ComQXPA-PsrfA QS system of Bacillus subtilis was harnessed and modified to create an upregulating QS circuit, in which the transcription of genes controlled by the PsrfA promoter may be promoted at high cell density. This QS circuit successfully activated the expression of green fluorescent protein (GFP) to 6.35-fold in a cell density-dependent manner in C. glutamicum. Next, the hfq-sRNA-mediated downregulating circuit under the control of the ComQXPA-PsrfA QS system was established, and the expression of GFP was autonomously repressed by 96.1%. Next, to fine-tune these two QS circuits, a library of synthetic PsrfA based promoters was constructed, and a series of mutant PsrfAM promoters with 0.4-1.5-fold strength of native PsrfA were selected. Subsequently, the ComQXPA-PsrfAM QS circuit was utilized to upregulate the expression of red fluorescent protein, and the same QS-based hfq-sRNA system was utilized to downregulate the expression of GFP simultaneously. Last, this bifunctional ComQXPA-PsrfAM QS circuit was verified again by fine-tuning the expression of α-amylase. Therefore, the engineered ComQXPA-PsrfAM QS cassette can be applied as a novel bifunctional QS circuit to flexibly control gene expression in C. glutamicum.
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Affiliation(s)
- Haiyan Liu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Feng Shi
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
- International Joint Laboratory on Food Safety, Jiangnan University, Wuxi 214122, China
| | - Shuyu Tan
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Xinping Yu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Wenmei Lai
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Yongfu Li
- National Engineering Laboratory for Cereal Fermentation Technology, Jiangnan University, Wuxi 214122, China
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Nasser A, Dallal MMS, Jahanbakhshi S, Azimi T, Nikouei L. Staphylococcus aureus: biofilm formation and strategies against it. Curr Pharm Biotechnol 2021; 23:664-678. [PMID: 34238148 DOI: 10.2174/1389201022666210708171123] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 05/09/2021] [Accepted: 05/31/2021] [Indexed: 11/22/2022]
Abstract
The formation of Staphylococcus aureus biofilm causes significant infections in the human body. Biofilm forms through the aggregation of bacterial species and brings about many complications. It mediates drug resistance and persistence and facilitates the recurrence of infection at the end of antimicrobial therapy. Biofilm formation goes through a series of steps to complete, and any interference in these steps can disrupt its formation. Such interference may occur at any stage of biofilm production, including attachment, monolayer formation, and accumulation. Interfering agents can act as quorum sensing inhibitors and interfere in the functionality of quorum sensing receptors, attachment inhibitors and affect the cell hydrophobicity. Among these inhibiting strategies, attachment inhibitors could serve as the best agents against biofilm formation. If pathogens abort the attachment, the following stages of biofilm formation, e.g., accumulation and dispersion, will fail to materialize. Inhibition at this stage leads to suppression of virulence factors and invasion. One of the best-known inhibitors is a chelator that collects metal, Fe+, Zn+, and magnesium critical for biofilm formation. These influential factors in the binding and formation of biofilm are investigated, and the coping strategy is discussed. This review examines the stages of biofilm formation and determines what factors interfere in the continuity of these steps. Finally, the inhibition strategies are investigated, reviewed, and discussed. Keywords: Biofilm, Staphylococcus, Biofilm inhibitor, Dispersion, Antibiofilm agent, EPS, PIA.
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Affiliation(s)
- Ahmad Nasser
- Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | | | - Shiva Jahanbakhshi
- Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Taher Azimi
- Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Leila Nikouei
- Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
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West KHJ, Shen W, Eisenbraun EL, Yang T, Vasquez JK, Horswill AR, Blackwell HE. Non-Native Peptides Capable of Pan-Activating the agr Quorum Sensing System across Multiple Specificity Groups of Staphylococcus epidermidis. ACS Chem Biol 2021; 16:1070-1078. [PMID: 33988969 DOI: 10.1021/acschembio.1c00240] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Staphylococcus epidermidis is a leading cause of hospital-acquired infections. Traditional antibiotics have significantly reduced efficacy against this pathogen due to its ability to form biofilms on abiotic surfaces and drug resistance. The accessory gene regulator (agr) quorum sensing system is directly involved in S. epidermidis pathogenesis. Activation of agr is achieved via binding of the autoinducing peptide (AIP) signal to the extracellular sensor domain of its cognate receptor, AgrC. Divergent evolution has given rise to four agr specificity groups in S. epidermidis defined by the unique AIP sequence used by each group (AIPs-I-IV) with observed cross-group activities. As agr agonism has been shown to reduce biofilm growth in S. epidermidis, the development of pan-group activators of the agr system is of interest as a potential antivirulence strategy. To date, no synthetic compounds have been identified that are capable of appreciably activating the agr system of more than one specificity group of S. epidermidis or, to our knowledge, of any of the other Staphylococci. Here, we report the characterization of the structure-activity relationships for agr agonism by S. epidermidis AIP-II and AIP-III and the application of these new SAR data and those previously reported for AIP-I for the design and synthesis of the first multigroup agr agonists. These non-native peptides were capable of inducing the expression of critical biofilm dispersal agents (i.e., phenol-soluble modulins) in cell culture and represent new tools to study the role of quorum sensing in S. epidermidis infections.
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Affiliation(s)
- Korbin H. J. West
- Department of Chemistry, University of Wisconsin−Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Wenqi Shen
- Department of Chemistry, University of Wisconsin−Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Emma L. Eisenbraun
- Department of Chemistry, University of Wisconsin−Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Tian Yang
- Department of Chemistry, University of Wisconsin−Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Joseph K. Vasquez
- Department of Chemistry, University of Wisconsin−Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Alexander R. Horswill
- Department of Immunology and Microbiology, Anschutz Medical Campus, University of Colorado, Aurora, Colorado 80045, United States
| | - Helen E. Blackwell
- Department of Chemistry, University of Wisconsin−Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
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40
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Grispoldi L, Karama M, Armani A, Hadjicharalambous C, Cenci-Goga BT. Staphylococcus aureus enterotoxin in food of animal origin and staphylococcal food poisoning risk assessment from farm to table. ITALIAN JOURNAL OF ANIMAL SCIENCE 2021. [DOI: 10.1080/1828051x.2020.1871428] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
| | - Musafiri Karama
- Department of Paraclinical Sciences, University of Pretoria, Onderstepoort, South Africa
| | - Andrea Armani
- Department of Veterinary Sciences, University of Pisa, Pisa, Italy
| | | | - Beniamino T. Cenci-Goga
- Department of Veterinary Medicine, Perugia, Italy
- Department of Paraclinical Sciences, University of Pretoria, Onderstepoort, South Africa
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41
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França A, Gaio V, Lopes N, Melo LDR. Virulence Factors in Coagulase-Negative Staphylococci. Pathogens 2021; 10:170. [PMID: 33557202 PMCID: PMC7913919 DOI: 10.3390/pathogens10020170] [Citation(s) in RCA: 65] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 01/29/2021] [Accepted: 01/29/2021] [Indexed: 12/13/2022] Open
Abstract
Coagulase-negative staphylococci (CoNS) have emerged as major pathogens in healthcare-associated facilities, being S. epidermidis, S. haemolyticus and, more recently, S. lugdunensis, the most clinically relevant species. Despite being less virulent than the well-studied pathogen S. aureus, the number of CoNS strains sequenced is constantly increasing and, with that, the number of virulence factors identified in those strains. In this regard, biofilm formation is considered the most important. Besides virulence factors, the presence of several antibiotic-resistance genes identified in CoNS is worrisome and makes treatment very challenging. In this review, we analyzed the different aspects involved in CoNS virulence and their impact on health and food.
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Affiliation(s)
- Angela França
- Laboratory of Research in Biofilms Rosário Oliveira, Centre of Biological Engineering, University of Minho, 4710-057 Braga, Portugal; (V.G.); (N.L.)
| | | | | | - Luís D. R. Melo
- Laboratory of Research in Biofilms Rosário Oliveira, Centre of Biological Engineering, University of Minho, 4710-057 Braga, Portugal; (V.G.); (N.L.)
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Schulze A, Mitterer F, Pombo JP, Schild S. Biofilms by bacterial human pathogens: Clinical relevance - development, composition and regulation - therapeutical strategies. MICROBIAL CELL (GRAZ, AUSTRIA) 2021; 8:28-56. [PMID: 33553418 PMCID: PMC7841849 DOI: 10.15698/mic2021.02.741] [Citation(s) in RCA: 70] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 01/08/2021] [Accepted: 01/12/2021] [Indexed: 12/19/2022]
Abstract
Notably, bacterial biofilm formation is increasingly recognized as a passive virulence factor facilitating many infectious disease processes. In this review we will focus on bacterial biofilms formed by human pathogens and highlight their relevance for diverse diseases. Along biofilm composition and regulation emphasis is laid on the intensively studied biofilms of Vibrio cholerae, Pseudomonas aeruginosa and Staphylococcus spp., which are commonly used as biofilm model organisms and therefore contribute to our general understanding of bacterial biofilm (patho-)physiology. Finally, therapeutical intervention strategies targeting biofilms will be discussed.
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Affiliation(s)
- Adina Schulze
- Institute of Molecular Biosciences, University of Graz, Humboldtstrasse 50, 8010 Graz, Austria
- A.S. and F.M. contributed equally to this work
| | - Fabian Mitterer
- Institute of Molecular Biosciences, University of Graz, Humboldtstrasse 50, 8010 Graz, Austria
- A.S. and F.M. contributed equally to this work
| | - Joao P. Pombo
- Institute of Molecular Biosciences, University of Graz, Humboldtstrasse 50, 8010 Graz, Austria
| | - Stefan Schild
- Institute of Molecular Biosciences, University of Graz, Humboldtstrasse 50, 8010 Graz, Austria
- BioTechMed Graz, Austria
- Field of Excellence Biohealth – University of Graz, Graz, Austria
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Liu B, Sun B. Rsp promotes the transcription of virulence factors in an agr-independent manner in Staphylococcus aureus. Emerg Microbes Infect 2020; 9:796-812. [PMID: 32248753 PMCID: PMC7241556 DOI: 10.1080/22221751.2020.1752116] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Staphylococcus aureus is a major human pathogen that causes a great diversity of community- and hospital-acquired infections. Rsp, a member of AraC/XylS family of transcriptional regulators (AFTRs), has been reported to play an important role in the regulation of virulence determinants in S. aureus via an agr-dependent pathway. Here we demonstrated that Rsp could bind to the rsp promoter to positively regulate its own expression. We then constructed an isogenic rsp deletion strain and compared the haemolysis in the wild-type and rsp mutant strains. Our results indicated that the rsp mutant strain displayed decreased haemolytic activity, which was correlated with a dramatic decrease in the expression of hla and psm. Furthermore, we analysed the regulatory effects of Rsp in the agr mutant strain and found that they are agr-independent. Electrophoretic mobility shift assay indicated that Rsp can directly bind to the promoter regions of hla and psm. The mouse model of subcutaneous abscess showed that the rsp mutant strain displayed a significant defect in virulence compared to the wild-type strain. These findings reveal that Rsp positively regulates the virulence of S. aureus by promoting the expression of hla and psm through direct binding to their promoter regions.
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Affiliation(s)
- Banghui Liu
- Department of Oncology, The First Affiliated Hospital, University of Science and Technology of China, Hefei, People's Republic of China
| | - Baolin Sun
- Department of Oncology, The First Affiliated Hospital, University of Science and Technology of China, Hefei, People's Republic of China
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Valeriani RG, Beard LL, Moller A, Ohtani K, Vidal JE. Gas gangrene-associated gliding motility is regulated by the Clostridium perfringens CpAL/VirSR system. Anaerobe 2020; 66:102287. [PMID: 33130105 DOI: 10.1016/j.anaerobe.2020.102287] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2020] [Revised: 10/01/2020] [Accepted: 10/21/2020] [Indexed: 11/29/2022]
Abstract
Clostridium perfringens strains cause a wide variety of human and animal disease, including gas gangrene or myonecrosis. Production of toxins required for myonecrosis, PFO and CPA, is regulated by the C. perfringens Agr-like (CpAL) system via the VirSR two-component system. Myonecrosis begins at the site of infection from where bacteria migrate deep into the host tissue likely using a previously described gliding motility phenotype. We therefore assessed whether gliding motility was under the control of the CpAL/VirSR regulon. The migration rate of myonecrosis-causing C. perfringens strain 13 (S13) was investigated during a 96 h period, including an adaptation phase with bacterial migration (∼1.4 mm/day) followed by a gliding phase allowing bacteria faster migration (∼8.6 mm/day). Gliding required both an intact CpAL system, and signaling through VirSR. Mutants lacking ΔagrB, or ΔvirR, were impaired for onward gliding while a complemented strain S13ΔagrB/pTS1303 had the gliding phenotype restored. Gene expression studies revealed upregulated transcription of pili genes (pilA1, pilA2 and pilT) whose encoded proteins were previously found to be required for gliding motility and CpAL/VirSR-regulated pfoA and cpa toxin genes. Compared to S13, transcription of cpa and pfoA significantly decreased in S13ΔagrB, or S13ΔvirR, strains but not that of pili genes. Further experiments demonstrated that mutants S13ΔpfoA and S13Δcpa migrated at the same rate as S13 wt. We demonstrated that CpAL/VirSR regulates C. perfringens gliding motility and that gliding bacteria have an increased transcription of toxin genes involved in myonecrosis.
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Affiliation(s)
| | - LaMonta L Beard
- Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Abraham Moller
- Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Kaori Ohtani
- Tokai University School of Medicine, Ishihara-shi, Kanagawa, Japan
| | - Jorge E Vidal
- Rollins School of Public Health, Emory University, Atlanta, GA, USA; Department of Microbiology and Immunology, University of Mississippi Medical Center, Jackson, MS, USA.
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Buch PJ, Chai Y, Goluch ED. Bacterial chatter in chronic wound infections. Wound Repair Regen 2020; 29:106-116. [PMID: 33047459 DOI: 10.1111/wrr.12867] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 08/07/2020] [Accepted: 10/06/2020] [Indexed: 11/29/2022]
Abstract
One of the hallmark characteristics of chronic diabetic wounds is the presence of biofilm-forming bacteria. Bacteria encapsulated in a biofilm may coexist as a polymicrobial community and communicate with each other through a phenomenon termed quorum sensing (QS). Here, we describe the QS circuits of bacterial species commonly found in chronic diabetic wounds. QS relies on diffusion of signaling molecules and the local concentration changes of these molecules that bacteria experience in wounds. These biochemical signaling pathways play a role not only in biofilm formation and virulence but also in wound healing. They are, therefore, key to understanding the distinctive nature of these infections. While several in vivo and in vitro models exist to study QS in wounds, there has been limited progress in understanding the interplay between QS molecules and host factors that contribute to wound healing. Lastly, we examine the potential of targeting QS for both diagnosis and therapeutic intervention purposes.
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Affiliation(s)
- Pranali J Buch
- Department of Chemical Engineering, Northeastern University, Boston, Massachusetts, USA
| | - Yunrong Chai
- Department of Biology, Northeastern University, Boston, Massachusetts, USA
| | - Edgar D Goluch
- Department of Chemical Engineering, Northeastern University, Boston, Massachusetts, USA.,Department of Biology, Northeastern University, Boston, Massachusetts, USA
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Etter D, Schelin J, Schuppler M, Johler S. Staphylococcal Enterotoxin C-An Update on SEC Variants, Their Structure and Properties, and Their Role in Foodborne Intoxications. Toxins (Basel) 2020; 12:E584. [PMID: 32927913 PMCID: PMC7551944 DOI: 10.3390/toxins12090584] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 09/07/2020] [Accepted: 09/08/2020] [Indexed: 12/20/2022] Open
Abstract
Staphylococcal enterotoxins are the most common cause of foodborne intoxications (staphylococcal food poisoning) and cause a wide range of diseases. With at least six variants staphylococcal enterotoxin C (SEC) stands out as particularly diverse amongst the 25 known staphylococcal enterotoxins. Some variants present unique and even host-specific features. Here, we review the role of SEC in human and animal health with a particular focus on its role as a causative agent for foodborne intoxications. We highlight structural features unique to SEC and its variants, particularly, the emetic and superantigen activity, as well as the roles of SEC in mastitis and in dairy products. Information about the genetic organization as well as regulatory mechanisms including the accessory gene regulator and food-related stressors are provided.
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Affiliation(s)
- Danai Etter
- Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zürich, 8057 Zürich, Switzerland;
- Laboratory of Food Microbiology, Institute of Food, Nutrition and Health, ETH Zürich, 8092 Zürich, Switzerland;
| | - Jenny Schelin
- Division of Applied Microbiology, Department of Chemistry, Lund University, 22100 Lund, Sweden;
| | - Markus Schuppler
- Laboratory of Food Microbiology, Institute of Food, Nutrition and Health, ETH Zürich, 8092 Zürich, Switzerland;
| | - Sophia Johler
- Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zürich, 8057 Zürich, Switzerland;
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Schilcher K, Horswill AR. Staphylococcal Biofilm Development: Structure, Regulation, and Treatment Strategies. Microbiol Mol Biol Rev 2020; 84:e00026-19. [PMID: 32792334 PMCID: PMC7430342 DOI: 10.1128/mmbr.00026-19] [Citation(s) in RCA: 284] [Impact Index Per Article: 71.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
In many natural and clinical settings, bacteria are associated with some type of biotic or abiotic surface that enables them to form biofilms, a multicellular lifestyle with bacteria embedded in an extracellular matrix. Staphylococcus aureus and Staphylococcus epidermidis, the most frequent causes of biofilm-associated infections on indwelling medical devices, can switch between an existence as single free-floating cells and multicellular biofilms. During biofilm formation, cells first attach to a surface and then multiply to form microcolonies. They subsequently produce the extracellular matrix, a hallmark of biofilm formation, which consists of polysaccharides, proteins, and extracellular DNA. After biofilm maturation into three-dimensional structures, the biofilm community undergoes a disassembly process that leads to the dissemination of staphylococcal cells. As biofilms are dynamic and complex biological systems, staphylococci have evolved a vast network of regulatory mechanisms to modify and fine-tune biofilm development upon changes in environmental conditions. Thus, biofilm formation is used as a strategy for survival and persistence in the human host and can serve as a reservoir for spreading to new infection sites. Moreover, staphylococcal biofilms provide enhanced resilience toward antibiotics and the immune response and impose remarkable therapeutic challenges in clinics worldwide. This review provides an overview and an updated perspective on staphylococcal biofilms, describing the characteristic features of biofilm formation, the structural and functional properties of the biofilm matrix, and the most important mechanisms involved in the regulation of staphylococcal biofilm formation. Finally, we highlight promising strategies and technologies, including multitargeted or combinational therapies, to eradicate staphylococcal biofilms.
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Affiliation(s)
- Katrin Schilcher
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Alexander R Horswill
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, Colorado, USA
- Department of Veterans Affairs Eastern Colorado Health Care System, Denver, Colorado, USA
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48
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Schilcher K, Horswill AR. Staphylococcal Biofilm Development: Structure, Regulation, and Treatment Strategies. Microbiol Mol Biol Rev 2020. [PMID: 32792334 DOI: 10.1128/mmbr.00026-19/asset/e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/15/2023] Open
Abstract
In many natural and clinical settings, bacteria are associated with some type of biotic or abiotic surface that enables them to form biofilms, a multicellular lifestyle with bacteria embedded in an extracellular matrix. Staphylococcus aureus and Staphylococcus epidermidis, the most frequent causes of biofilm-associated infections on indwelling medical devices, can switch between an existence as single free-floating cells and multicellular biofilms. During biofilm formation, cells first attach to a surface and then multiply to form microcolonies. They subsequently produce the extracellular matrix, a hallmark of biofilm formation, which consists of polysaccharides, proteins, and extracellular DNA. After biofilm maturation into three-dimensional structures, the biofilm community undergoes a disassembly process that leads to the dissemination of staphylococcal cells. As biofilms are dynamic and complex biological systems, staphylococci have evolved a vast network of regulatory mechanisms to modify and fine-tune biofilm development upon changes in environmental conditions. Thus, biofilm formation is used as a strategy for survival and persistence in the human host and can serve as a reservoir for spreading to new infection sites. Moreover, staphylococcal biofilms provide enhanced resilience toward antibiotics and the immune response and impose remarkable therapeutic challenges in clinics worldwide. This review provides an overview and an updated perspective on staphylococcal biofilms, describing the characteristic features of biofilm formation, the structural and functional properties of the biofilm matrix, and the most important mechanisms involved in the regulation of staphylococcal biofilm formation. Finally, we highlight promising strategies and technologies, including multitargeted or combinational therapies, to eradicate staphylococcal biofilms.
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Affiliation(s)
- Katrin Schilcher
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Alexander R Horswill
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, Colorado, USA
- Department of Veterans Affairs Eastern Colorado Health Care System, Denver, Colorado, USA
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Butrico CE, Cassat JE. Quorum Sensing and Toxin Production in Staphylococcus aureus Osteomyelitis: Pathogenesis and Paradox. Toxins (Basel) 2020; 12:toxins12080516. [PMID: 32806558 PMCID: PMC7471978 DOI: 10.3390/toxins12080516] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2020] [Revised: 08/04/2020] [Accepted: 08/10/2020] [Indexed: 01/18/2023] Open
Abstract
Staphylococcus aureus is a Gram-positive pathogen capable of infecting nearly every vertebrate organ. Among these tissues, invasive infection of bone (osteomyelitis) is particularly common and induces high morbidity. Treatment of osteomyelitis is notoriously difficult and often requires debridement of diseased bone in conjunction with prolonged antibiotic treatment to resolve infection. During osteomyelitis, S. aureus forms characteristic multicellular microcolonies in distinct niches within bone. Virulence and metabolic responses within these multicellular microcolonies are coordinated, in part, by quorum sensing via the accessory gene regulator (agr) locus, which allows staphylococcal populations to produce toxins and adapt in response to bacterial density. During osteomyelitis, the Agr system significantly contributes to dysregulation of skeletal homeostasis and disease severity but may also paradoxically inhibit persistence in the host. Moreover, the Agr system is subject to complex crosstalk with other S. aureus regulatory systems, including SaeRS and SrrAB, which can significantly impact the progression of osteomyelitis. The objective of this review is to highlight Agr regulation, its implications on toxin production, factors that affect Agr activation, and the potential paradoxical influences of Agr regulation on disease progression during osteomyelitis.
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Affiliation(s)
- Casey E. Butrico
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN 37232, USA;
| | - James E. Cassat
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN 37232, USA;
- Department of Pediatrics, Division of Pediatric Infectious Diseases, Vanderbilt University Medical Center, Nashville, TN 37232, USA
- Vanderbilt Center for Bone Biology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
- Department of Biomedical Engineering, Vanderbilt University, Nashville, TN 37232, USA
- Vanderbilt Institute for Infection, Immunology, and Inflammation (VI4), Vanderbilt University Medical Center, Nashville, TN 37232, USA
- Correspondence: ; Tel.: +1-615-936-6494
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Microbial biofilm ecology, in silico study of quorum sensing receptor-ligand interactions and biofilm mediated bioremediation. Arch Microbiol 2020; 203:13-30. [PMID: 32785735 DOI: 10.1007/s00203-020-02012-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Revised: 07/17/2020] [Accepted: 08/04/2020] [Indexed: 12/15/2022]
Abstract
Biofilms are structured microbial communities of single or multiple populations in which microbial cells adhere to a surface and get embedded in extracellular polymeric substances (EPS). This review attempts to explain biofilm architecture, development phases, and forces that drive bacteria to promote biofilm mode of growth. Bacterial chemical communication, also known as Quorum sensing (QS), which involves the production, detection, and response to small molecules called autoinducers, is highlighted. The review also provides a brief outline of interspecies and intraspecies cell-cell communication. Additionally, we have performed docking studies using Discovery Studio 4.0, which has enabled our understanding of the prominent interactions between autoinducers and their receptors in different bacterial species while also scoring their interaction energies. Receptors, such as LuxN (Phosphoreceiver domain and RecA domain), LuxP, and LuxR, interacted with their ligands (AI-1, AI-2, and AHL) with a CDocker interaction energy of - 31.6083 kcal/mole; - 34.5821 kcal/mole, - 48.2226 kcal/mole and - 41.5885 kcal/mole, respectively. Since biofilms are ideal for the remediation of contaminants due to their high microbial biomass and their potential to immobilize pollutants, this article also provides an overview of biofilm-mediated bioremediation.
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