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Cruz AAD, Cabeo M, Durán-Viseras A, Sampedro I, Llamas I. Interference of AHL signal production in the phytophatogen Pantoea agglomerans as a sustainable biological strategy to reduce its virulence. Microbiol Res 2024; 285:127781. [PMID: 38795406 DOI: 10.1016/j.micres.2024.127781] [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: 02/25/2024] [Revised: 04/23/2024] [Accepted: 05/21/2024] [Indexed: 05/28/2024]
Abstract
Pantoea agglomerans is considered one of the most ubiquitous and versatile organisms that include strains that induce diseases in various crops and occasionally cause opportunistic infections in humans. To develop effective strategies to mitigate its impact on plant health and agricultural productivity, a comprehensive investigation is crucial for better understanding its pathogenicity. One proposed eco-friendly approach involves the enzymatic degradation of quorum sensing (QS) signal molecules like N-acylhomoserine lactones (AHLs), known as quorum quenching (QQ), offering potential treatment for such bacterial diseases. In this study the production of C4 and 3-oxo-C6HSL was identified in the plant pathogenic P. agglomerans CFBP 11141 and correlated to enzymatic activities such as amylase and acid phosphatase. Moreover, the heterologous expression of a QQ enzyme in the pathogen resulted in lack of AHLs production and the attenuation of the virulence by mean of drastically reduction of soft rot disease in carrots and cherry tomatoes. Additionally, the interference with the QS systems of P. agglomerans CFBP 11141 by two the plant growth-promoting and AHL-degrading bacteria (PGP-QQ) Pseudomonas segetis P6 and Bacillus toyonensis AA1EC1 was evaluated as a potential biocontrol approach for the first time. P. segetis P6 and B. toyonensis AA1EC1 demonstrated effectiveness in diminishing soft rot symptoms induced by P. agglomerans CFBP 11141 in both carrots and cherry tomatoes. Furthermore, the virulence of pathogen notably decreased when co-cultured with strain AA1EC1 on tomato plants.
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Affiliation(s)
- Alba Amaro-da Cruz
- Department of Microbiology, Faculty of Pharmacy, Cartuja Campus, University of Granada, Granada 18071, Spain
| | - Mónica Cabeo
- Department of Microbiology, Faculty of Pharmacy, Cartuja Campus, University of Granada, Granada 18071, Spain
| | - Ana Durán-Viseras
- Department of Microbiology, Faculty of Pharmacy, Cartuja Campus, University of Granada, Granada 18071, Spain
| | - Inmaculada Sampedro
- Department of Microbiology, Faculty of Pharmacy, Cartuja Campus, University of Granada, Granada 18071, Spain; Institute of Biotechnology, Biomedical Research Center (CIBM), University of Granada, Granada 18106, Spain.
| | - Inmaculada Llamas
- Department of Microbiology, Faculty of Pharmacy, Cartuja Campus, University of Granada, Granada 18071, Spain; Institute of Biotechnology, Biomedical Research Center (CIBM), University of Granada, Granada 18106, Spain.
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Gonzales M, Jacquet P, Gaucher F, Chabrière É, Plener L, Daudé D. AHL-Based Quorum Sensing Regulates the Biosynthesis of a Variety of Bioactive Molecules in Bacteria. JOURNAL OF NATURAL PRODUCTS 2024. [PMID: 38390739 DOI: 10.1021/acs.jnatprod.3c00672] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/24/2024]
Abstract
Bacteria are social microorganisms that use communication systems known as quorum sensing (QS) to regulate diverse cellular behaviors including the production of various secreted molecules. Bacterial secondary metabolites are widely studied for their bioactivities including antibiotic, antifungal, antiparasitic, and cytotoxic compounds. Besides playing a crucial role in natural bacterial niches and intermicrobial competition by targeting neighboring organisms and conferring survival advantages to the producer, these bioactive molecules may be of prime interest to develop new antimicrobials or anticancer therapies. This review focuses on bioactive compounds produced under acyl homoserine lactone-based QS regulation by Gram-negative bacteria that are pathogenic to humans and animals, including the Burkholderia, Serratia, Pseudomonas, Chromobacterium, and Pseudoalteromonas genera. The synthesis, regulation, chemical nature, biocidal effects, and potential applications of these identified toxic molecules are presented and discussed in light of their role in microbial interactions.
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Affiliation(s)
- Mélanie Gonzales
- Aix Marseille Université, IRD, APHM, MEPHI, IHU-Méditerranée Infection, Marseille 13288, France
- Gene&GreenTK, Marseille 13005, France
| | | | | | - Éric Chabrière
- Aix Marseille Université, IRD, APHM, MEPHI, IHU-Méditerranée Infection, Marseille 13288, France
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Mao S, Li Q, Yang Z, Li Y, Ye X, Wang H. Design, synthesis, and biological evaluation of benzoheterocyclic sulfoxide derivatives as quorum sensing inhibitors in Pseudomonas aeruginosa. J Enzyme Inhib Med Chem 2023; 38:2175820. [PMID: 36748317 PMCID: PMC9930800 DOI: 10.1080/14756366.2023.2175820] [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] [Indexed: 02/08/2023] Open
Abstract
Six series of benzoheterocyclic sulfoxide derivatives were designed and synthesised as Pseudomonas aeruginosa (P. aeruginosa) quorum sensing inhibitors in this paper. We experimentally demonstrated that 6b significantly inhibited the formation of P. aeruginosa PAO1 biofilm without affecting the growth. Further mechanistic studies showed that 6b affected the luminescence of quorum sensing reported strain PAO1-lasB-gfp and the production of P. aeruginosa PAO1 elastase virulence factor which was regulated by las system. These experimental results indicate that 6b acts as a quorum sensing inhibitor mainly through the las system. Furthermore, silico molecular docking studies demonstrated that 6b and the P. aeruginosa quorum sensing receptor LasR were molecularly bound via hydrogen bonding interactions. Preliminary structure-activity relationship and docking studies illustrated that 6b shows great promise as anti-biofilm compounds for further studies in order to solve the problem of microbial resistance in future.
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Affiliation(s)
- Shen Mao
- College of Pharmaceutical Science & Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou, P. R. China
| | - Qiaoqiang Li
- College of Pharmaceutical Science & Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou, P. R. China
| | - Zhikun Yang
- College of Pharmaceutical Science & Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou, P. R. China
| | - Yasheng Li
- Department of Infectious Diseases, The First Affiliated Hospital of Anhui Medical University & Anhui Center for Surveillance of Bacterial Resistance, Hefei, P. R. China
| | - Xinyi Ye
- College of Pharmaceutical Science & Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou, P. R. China,Xinyi Ye College of Pharmaceutical Science & Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou310014, P. R. China
| | - Hong Wang
- College of Pharmaceutical Science & Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou, P. R. China,CONTACT Hong Wang
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Peng B, Li Y, Yin J, Ding W, Fazuo W, Xiao Z, Yin H. A bibliometric analysis on discovering anti-quorum sensing agents against clinically relevant pathogens: current status, development, and future directions. Front Microbiol 2023; 14:1297843. [PMID: 38098670 PMCID: PMC10720721 DOI: 10.3389/fmicb.2023.1297843] [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: 09/20/2023] [Accepted: 11/10/2023] [Indexed: 12/17/2023] Open
Abstract
Background Quorum sensing is bacteria's ability to communicate and regulate their behavior based on population density. Anti-quorum sensing agents (anti-QSA) is promising strategy to treat resistant infections, as well as reduce selective pressure that leads to antibiotic resistance of clinically relevant pathogens. This study analyzes the output, hotspots, and trends of research in the field of anti-QSA against clinically relevant pathogens. Methods The literature on anti-QSA from the Web of Science Core Collection database was retrieved and analyzed. Tools such as CiteSpace and Alluvial Generator were used to visualize and interpret the data. Results From 1998 to 2023, the number of publications related to anti-QAS research increased rapidly, with a total of 1,743 articles and reviews published in 558 journals. The United States was the largest contributor and the most influential country, with an H-index of 88, higher than other countries. Williams was the most productive author, and Hoiby N was the most cited author. Frontiers in Microbiology was the most prolific and the most cited journal. Burst detection indicated that the main frontier disciplines shifted from MICROBIOLOGY, CLINICAL, MOLECULAR BIOLOGY, and other biomedicine-related fields to FOOD, MATERIALS, NATURAL PRODUCTS, and MULTIDISCIPLINARY. In the whole research history, the strongest burst keyword was cystic-fibrosis patients, and the strongest burst reference was Lee and Zhang (2015). In the latest period (burst until 2023), the strongest burst keyword was silver nanoparticle, and the strongest burst reference was Whiteley et al. (2017). The co-citation network revealed that the most important interest and research direction was anti-biofilm/anti-virulence drug development, and timeline analysis suggested that this direction is also the most active. The key concepts alluvial flow visualization revealed seven terms with the longest time span and lasting until now, namely Escherichia coli, virulence, Pseudomonas aeruginosa, virulence factor, bacterial biofilm, gene expression, quorum sensing. Comprehensive analysis shows that nanomaterials, marine natural products, and artificial intelligence (AI) may become hotspots in the future. Conclusion This bibliometric study reveals the current status and trends of anti-QSA research and may assist researchers in identifying hot topics and exploring new research directions.
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Affiliation(s)
- Bo Peng
- Institute for Environmental and Climate Research, Jinan University, Guangzhou, China
| | - Yanqun Li
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, China
| | - Jiajia Yin
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, China
| | - Wenping Ding
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China
| | - Wang Fazuo
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, China
| | - Zhihui Xiao
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, China
| | - Hao Yin
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, China
- Sanya Institute of Ocean Eco-Environmental Engineering, Sanya, China
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Kao AB, Hund AK, Santos FP, Young JG, Bhat D, Garland J, Oomen RA, McCreery HF. Opposing Responses to Scarcity Emerge from Functionally Unique Sociality Drivers. Am Nat 2023; 202:302-321. [PMID: 37606948 DOI: 10.1086/725426] [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] [Indexed: 08/23/2023]
Abstract
AbstractFrom biofilms to whale pods, organisms across taxa live in groups, thereby accruing numerous diverse benefits of sociality. All social organisms, however, pay the inherent cost of increased resource competition. One expects that when resources become scarce, this cost will increase, causing group sizes to decrease. Indeed, this occurs in some species, but there are also species for which group sizes remain stable or even increase under scarcity. What accounts for these opposing responses? We present a conceptual framework, literature review, and theoretical model demonstrating that differing responses to sudden resource shifts can be explained by which sociality benefit exerts the strongest selection pressure on a particular species. We categorize resource-related benefits of sociality into six functionally distinct classes and model their effect on the survival of individuals foraging in groups under different resource conditions. We find that whether, and to what degree, the optimal group size (or correlates thereof) increases, decreases, or remains constant when resource abundance declines depends strongly on the dominant sociality mechanism. Existing data, although limited, support our model predictions. Overall, we show that across a wide diversity of taxa, differences in how group size shifts in response to resource declines can be driven by differences in the primary benefits of sociality.
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Das A, Patro S, Simnani FZ, Singh D, Sinha A, Kumari K, Rao PV, Singh S, Kaushik NK, Panda PK, Suar M, Verma SK. Biofilm modifiers: The disparity in paradigm of oral biofilm ecosystem. Biomed Pharmacother 2023; 164:114966. [PMID: 37269809 DOI: 10.1016/j.biopha.2023.114966] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 05/19/2023] [Accepted: 05/29/2023] [Indexed: 06/05/2023] Open
Abstract
A biofilm is a population of sessile microorganisms that has a distinct organized structure and characteristics like channels and projections. Good oral hygiene and reduction in the prevalence of periodontal diseases arise from minimal biofilm accumulation in the mouth, however, studies focusing on modifying the ecology of oral biofilms have not yet been consistently effective. The self-produced matrix of extracellular polymeric substances and greater antibiotic resistance make it difficult to target and eliminate biofilm infections, which lead to serious clinical consequences that are often lethal. Therefore, a better understanding is required to target and modify the ecology of biofilms in order to eradicate the infection, not only in instances of oral disorders but also in terms of nosocomial infections. The review focuses on several biofilm ecology modifiers to prevent biofilm infections, as well as the involvement of biofilm in antibiotic resistance, implants or in-dwelling device contamination, dental caries, and other periodontal disorders. It also discusses recent advances in nanotechnology that may lead to novel strategies for preventing and treating infections caused by biofilms as well as a novel outlook to infection control.
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Affiliation(s)
- Antarikshya Das
- KIIT School of Dental Sciences, KIIT University, Bhubaneswar 751024, Odisha, India
| | - Swadheena Patro
- KIIT School of Dental Sciences, KIIT University, Bhubaneswar 751024, Odisha, India.
| | | | - Dibyangshee Singh
- KIIT School of Biotechnology, KIIT University, Bhubaneswar 751024, Odisha, India
| | - Adrija Sinha
- KIIT School of Biotechnology, KIIT University, Bhubaneswar 751024, Odisha, India
| | - Khushbu Kumari
- KIIT School of Dental Sciences, KIIT University, Bhubaneswar 751024, Odisha, India
| | - Patnala Vedika Rao
- KIIT School of Medical Sciences, KIIT University, Bhubaneswar 751024, Odisha, India
| | - Sarita Singh
- BVG Life Sciences Limited, Sagar Complex, Old Pune-Mumbai Road, Chinchwad, Pune 411034, India
| | - Nagendra Kumar Kaushik
- Plasma Bioscience Research Center, Department of Electrical and Biological Physics, Kwangwoon University, 01897 Seoul, Republic of Korea.
| | - Pritam Kumar Panda
- Condensed Matter Theory Group, Materials Theory Division, Department of Physics and Astronomy, Uppsala University, Box 516, SE-751 20 Uppsala, Sweden.
| | - Mrutyunjay Suar
- KIIT School of Dental Sciences, KIIT University, Bhubaneswar 751024, Odisha, India.
| | - Suresh K Verma
- KIIT School of Dental Sciences, KIIT University, Bhubaneswar 751024, Odisha, India.
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7
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Ye X, Mao S, Li Y, Yang Z, Du A, Wang H. Design, Synthesis, and Biological Evaluation of Phenyloxadiazole Sulfoxide Derivatives as Potent Pseudomonas aeruginosa Biofilm Inhibitors. Molecules 2023; 28:molecules28093879. [PMID: 37175289 PMCID: PMC10180516 DOI: 10.3390/molecules28093879] [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: 04/01/2023] [Revised: 04/25/2023] [Accepted: 04/28/2023] [Indexed: 05/15/2023] Open
Abstract
With the development of antimicrobial agents, researchers have developed new strategies through key regulatory systems to block the expression of virulence genes without affecting bacterial growth. This strategy can minimize the selective pressure that leads to the emergence of resistance. Quorum sensing (QS) is an intercellular communication system that plays a key role in the regulation of bacterial virulence and biofilm formation. Studies have revealed that the QS system controls 4-6% of the total number of P. aeruginosa genes, and quorum sensing inhibitors (QSIs) could be a promising target for developing new prevention and treatment strategies against P. aeruginosa infection. In this study, four series of phenyloxadiazole and phenyltetrazole sulfoxide derivatives were synthesized and evaluated for their inhibitory effects on P. aeruginosa PAO1 biofilm formation. Our results showed that 5b had biofilm inhibitory activity and reduced the production of QS-regulated virulence factors in P. aeruginosa. In addition, silico molecular docking studies have shown that 5b binds to the P. aeruginosa QS receptor protein LasR through hydrogen bond interaction. Preliminary structure-activity relationship and docking studies show that 5b has broad application prospects as an anti-biofilm compound, and further research will be carried out in the future to solve the problem of microbial resistance.
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Affiliation(s)
- Xinyi Ye
- Key Laboratory of Marine Fishery Resources Exploitment & Utilization of Zhejiang Province, College of Pharmaceutical Science & Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou 310014, China
| | - Shen Mao
- Key Laboratory of Marine Fishery Resources Exploitment & Utilization of Zhejiang Province, College of Pharmaceutical Science & Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou 310014, China
| | - Yasheng Li
- Key Laboratory of Marine Fishery Resources Exploitment & Utilization of Zhejiang Province, College of Pharmaceutical Science & Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou 310014, China
| | - Zhikun Yang
- Key Laboratory of Marine Fishery Resources Exploitment & Utilization of Zhejiang Province, College of Pharmaceutical Science & Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou 310014, China
| | - Aoqi Du
- Key Laboratory of Marine Fishery Resources Exploitment & Utilization of Zhejiang Province, College of Pharmaceutical Science & Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou 310014, China
| | - Hong Wang
- Key Laboratory of Marine Fishery Resources Exploitment & Utilization of Zhejiang Province, College of Pharmaceutical Science & Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou 310014, China
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8
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Usinowicz J, O'Connor MI. The fitness value of ecological information in a variable world. Ecol Lett 2023; 26:621-639. [PMID: 36849871 DOI: 10.1111/ele.14166] [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: 09/16/2021] [Revised: 12/08/2022] [Accepted: 12/08/2022] [Indexed: 03/01/2023]
Abstract
Information processing is increasingly recognized as a fundamental component of life in variable environments, including the evolved use of environmental cues, biomolecular networks, and social learning. Despite this, ecology lacks a quantitative framework for understanding how population, community, and ecosystem dynamics depend on information processing. Here, we review the rationale and evidence for 'fitness value of information' (FVOI), and synthesize theoretical work in ecology, information theory, and probability behind this general mathematical framework. The FVOI quantifies how species' per capita population growth rates can depend on the use of information in their environment. FVOI is a breakthrough approach to linking information processing and ecological and evolutionary outcomes in a changing environment, addressing longstanding questions about how information mediates the effects of environmental change and species interactions.
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Affiliation(s)
- Jacob Usinowicz
- Department of Zoology, University of British Columbia, Vancouver, Canada
- Biodiversity Research Centre, University of British Columbia, Vancouver, Canada
| | - Mary I O'Connor
- Department of Zoology, University of British Columbia, Vancouver, Canada
- Biodiversity Research Centre, University of British Columbia, Vancouver, Canada
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Echlin M, Aguilar B, Shmulevich I. Characterizing the Impact of Communication on Cellular and Collective Behavior Using a Three-Dimensional Multiscale Cellular Model. ENTROPY (BASEL, SWITZERLAND) 2023; 25:319. [PMID: 36832685 PMCID: PMC9955575 DOI: 10.3390/e25020319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 01/29/2023] [Accepted: 02/06/2023] [Indexed: 06/18/2023]
Abstract
Communication between cells enables the coordination that drives structural and functional complexity in biological systems. Both single and multicellular organisms have evolved diverse communication systems for a range of purposes, including synchronization of behavior, division of labor, and spatial organization. Synthetic systems are also increasingly being engineered to utilize cell-cell communication. While research has elucidated the form and function of cell-cell communication in many biological systems, our knowledge is still limited by the confounding effects of other biological phenomena at play and the bias of the evolutionary background. In this work, our goal is to push forward the context-free understanding of what impact cell-cell communication can have on cellular and population behavior to more fully understand the extent to which cell-cell communication systems can be utilized, modified, and engineered. We use an in silico model of 3D multiscale cellular populations, with dynamic intracellular networks interacting via diffusible signals. We focus on two key communication parameters: the effective interaction distance at which cells are able to interact and the receptor activation threshold. We found that cell-cell communication can be divided into six different forms along the parameter axes, three asocial and three social. We also show that cellular behavior, tissue composition, and tissue diversity are all highly sensitive to both the general form and specific parameters of communication even when the cellular network has not been biased towards that behavior.
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Affiliation(s)
- Moriah Echlin
- Prostate Cancer Research Center, Faculty of Medicine and Health Technology, Tampere University, FI-33014 Tampere, Finland
- Institute for Systems Biology, Seattle, WA 98109, USA
| | - Boris Aguilar
- Institute for Systems Biology, Seattle, WA 98109, USA
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10
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Cheng C, Yan X, Liu B, Jiang T, Zhou Z, Guo F, Zhang Q, Li C, Fang T. SdiA Enhanced the Drug Resistance of Cronobacter sakazakii and Suppressed Its Motility, Adhesion and Biofilm Formation. Front Microbiol 2022; 13:901912. [PMID: 35602061 PMCID: PMC9120920 DOI: 10.3389/fmicb.2022.901912] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Accepted: 04/19/2022] [Indexed: 11/13/2022] Open
Abstract
Cronobacter sakazakii is a common foodborne pathogen, and the mortality rate of its infection is as high as 40–80%. SdiA acts as a quorum sensing regulator in many foodborne pathogens, but its role in C. sakazakii remains unclear. Here, we further determined the effect of the sdiA gene in C. sakazakii pathogenicity. The SdiA gene in C. sakazakii was knocked out by gene editing technology, and the biological characteristics of the ΔsdiA mutant of C. sakazakii were studied, followed by transcriptome analysis to elucidate its effects. The results suggested that SdiA gene enhanced the drug resistance of C. sakazakii but diminished its motility, adhesion and biofilm formation ability and had no effect on its growth. Transcriptome analysis showed that the ΔsdiA upregulated the expression levels of D-galactose operon genes (including dgoR, dgoK, dgoA, dgoD and dgoT) and flagella-related genes (FliA and FliC) in C. sakazakii and downregulated the expression levels of related genes in the type VI secretion system (VasK gene was downregulated by 1.53-fold) and ABC transport system (downregulated by 1.5-fold), indicating that SdiA gene was related to the physiological metabolism of C. sakazakii. The results were useful for clarifying the pathogenic mechanism of C. sakazakii and provide a theoretical basis for controlling bacterial infection.
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Azimi S, Lewin GR, Whiteley M. The biogeography of infection revisited. Nat Rev Microbiol 2022; 20:579-592. [PMID: 35136217 PMCID: PMC9357866 DOI: 10.1038/s41579-022-00683-3] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/04/2022] [Indexed: 01/01/2023]
Abstract
Many microbial communities, including those involved in chronic human infections, are patterned at the micron scale. In this Review, we summarize recent work that has defined the spatial arrangement of microorganisms in infection and begun to demonstrate how changes in spatial patterning correlate with disease. Advances in microscopy have refined our understanding of microbial micron-scale biogeography in samples from humans. These findings then serve as a benchmark for studying the role of spatial patterning in preclinical models, which provide experimental versatility to investigate the interplay between biogeography and pathogenesis. Experimentation using preclinical models has begun to show how spatial patterning influences the interactions between cells, their ability to coexist, their virulence and their recalcitrance to treatment. Future work to study the role of biogeography in infection and the functional biogeography of microorganisms will further refine our understanding of the interplay of spatial patterning, pathogen virulence and disease outcomes.
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Affiliation(s)
- Sheyda Azimi
- School of Biological Sciences and Center for Microbial Dynamics and Infection, Georgia Institute of Technology, Atlanta, GA, USA
| | - Gina R Lewin
- Emory-Children's Cystic Fibrosis Center, Atlanta, GA, USA
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12
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Quorum Sensing Regulation of Virulence Gene Expression in Vibrio harveyi during its Interaction with Marine Diatom Skeletonema marinoi. JOURNAL OF PURE AND APPLIED MICROBIOLOGY 2021. [DOI: 10.22207/jpam.15.4.78] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Communication between species from different kingdoms may be as important as intra-kingdom communication. It has recently been confirmed that co-existing bacteria and phytoplankton in aquatic ecosystems do cross-talk. This study examined the signs of possible cross signalling between V. harveyi, one of the predominant bacterial species of the marine ecosystem and a dominant diatom species, S.marinoi, to understand communication over species borders. It is known that V.harveyi employ quorum sensing for cell-to-cell communication, bioluminescence (luxR), and the regulation of the virulence gene (vhp, chiA). Former studies have also shown, this kind of interactions being disrupted by compounds secreted by a few algal species existing in the aquatic ecosystem. We investigated the QS communication by quantifying the expression levels of virulence regulator luxR and virulence factors metalloprotease (vhp) and chitinase (chiA) in four different V. harveyi strains grown in the presence of S. marinoi strain. Results obtained in this study indicate that quorum sensing was activated in strains of V. harveyi analysed but did not regulate the expressions of vhp and chiA virulence factors. This observation suggests that the existence of S. marinoi did not interfere with the QS behaviour of V. harveyi and its interaction with marine diatom; it may be due to the commensalism relationship.
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13
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Antibiotic resistance related to biofilm formation in Streptococcus suis. Appl Microbiol Biotechnol 2020; 104:8649-8660. [PMID: 32897417 DOI: 10.1007/s00253-020-10873-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 08/23/2020] [Accepted: 08/31/2020] [Indexed: 12/13/2022]
Abstract
Streptococcus suis (S. suis) is an important zoonotic agent, which seriously impacts the pig industry and human health in various countries. Biofilm formation is likely contributing to the virulence and drug resistance in S. suis. A better knowledge of biofilm formation as well as to biofilm-dependent drug resistance mechanisms in S. suis can be of great significance for the prevention and treatment of S. suis infections. This literature review updates the latest scientific data related to biofilm formation in S. suis and its impact on drug tolerance and resistance.Key points• Biofilm formation is the important reasons for drug resistance of SS infections.• The review includes the regulatory mechanism of SS biofilm formation.• The review includes the drug resistance mechanisms of SS biofilm.
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Chen J, Lu Y, Ye X, Emam M, Zhang H, Wang H. Current advances in Vibrio harveyi quorum sensing as drug discovery targets. Eur J Med Chem 2020; 207:112741. [PMID: 32871343 DOI: 10.1016/j.ejmech.2020.112741] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2020] [Revised: 07/16/2020] [Accepted: 07/26/2020] [Indexed: 12/25/2022]
Abstract
Vibrio harveyi is a marine bacterial pathogen which infects a wide range of marine organisms and results in severe loss. Antibiotics have been used for prophylaxis and treatment of V. harveyi infection. However, antibiotic resistance is a major public health threat to both human and animals. Therefore, there is an urgent need for novel antimicrobial agents with new modes of action. In V. harveyi, many virulence factors production and bioluminescence formation depend on its quorum sensing (QS) network. Therefore, the QS system has been widely investigated as an effective potential target for the treatment of V. harveyi infection. This perspective focuses on the quorum sensing inhibitors (QSIs) of V. harveyi QS systems (LuxM/N, LuxS/PQ, and CqsA/S) and evaluates medicinal chemistry strategies.
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Affiliation(s)
- Jianwei Chen
- College of Pharmaceutical Science & Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou, 310014, China
| | - Yaojia Lu
- College of Pharmaceutical Science & Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou, 310014, China
| | - Xinyi Ye
- College of Pharmaceutical Science & Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou, 310014, China
| | - Mahmoud Emam
- College of Pharmaceutical Science & Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou, 310014, China; Phytochemistry and Plant Systematics Department, National Research Centre, 33 El Bohouth St., Dokki, Giza, 12622, Egypt
| | - Huawei Zhang
- College of Pharmaceutical Science & Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou, 310014, China
| | - Hong Wang
- College of Pharmaceutical Science & Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou, 310014, China.
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15
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Optimal Response to Quorum-Sensing Signals Varies in Different Host Environments with Different Pathogen Group Size. mBio 2020; 11:mBio.00535-20. [PMID: 32487754 PMCID: PMC7267880 DOI: 10.1128/mbio.00535-20] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Quorum sensing describes the ability of microbes to alter gene regulation according to their local population size. Some successful theory suggests that this is a form of cooperation, namely, investment in shared products is only worthwhile if there are sufficient bacteria making the same product. This theory can explain the genetic diversity in these signaling systems in Gram-positive bacteria, such as Bacillus and Staphylococcus sp. The possible advantages gained by rare genotypes (which can exploit the products of their more common neighbors) could explain why different genotypes can coexist. We show that while these social interactions can occur in simple laboratory experiments, they do not occur in naturalistic infections using an invertebrate pathogen, Bacillus thuringiensis. Instead, our results suggest that different genotypes are adapted to differently sized hosts. Overall, social models are not easily applied to this system, implying that a different explanation for this form of quorum sensing is required. The persistence of genetic variation in master regulators of gene expression, such as quorum-sensing systems, is hard to explain. Here, we investigated two alternative hypotheses for the prevalence of polymorphic quorum sensing in Gram-positive bacteria, i.e., the use of different signal/receptor pairs (‘pherotypes’) to regulate the same functions. First, social interactions between pherotypes or ‘facultative cheating’ may favor rare variants that exploit the signals of others. Second, different pherotypes may increase fitness in different environments. We evaluated these hypotheses in the invertebrate pathogen Bacillus thuringiensis, using three pherotypes expressed in a common genetic background. Facultative cheating could occur in well-mixed host homogenates provided there was minimal cross talk between competing pherotypes. However, facultative cheating did not occur when spatial structure was increased in static cultures or in naturalistic oral infections, where common pherotypes had higher fitness. There was clear support for environment-dependent fitness; pherotypes varied in responsiveness to signals and in mean competitive fitness. Notably, competitive fitness varied with group size. In contrast to typical social evolution models of quorum sensing which predict higher response to signal at larger group size, the pherotype with highest responsiveness to signals performed best in smaller hosts where infections have a lower pathogen group size. In this system, low signal abundance appears to limit fitness in hosts, while the optimal level of response to signals varies in different host environments.
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16
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Hernando-Amado S, Alcalde-Rico M, Gil-Gil T, Valverde JR, Martínez JL. Naringenin Inhibition of the Pseudomonas aeruginosa Quorum Sensing Response Is Based on Its Time-Dependent Competition With N-(3-Oxo-dodecanoyl)-L-homoserine Lactone for LasR Binding. Front Mol Biosci 2020; 7:25. [PMID: 32181260 PMCID: PMC7059128 DOI: 10.3389/fmolb.2020.00025] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Accepted: 02/07/2020] [Indexed: 12/23/2022] Open
Abstract
Bacterial quorum sensing (QS) is a cell-to-cell communication system that governs the expression of a large set of genes involved in bacterial-host interactions, including the production of virulence factors. Conversely, the hosts can produce anti-QS compounds to impair virulence of bacterial pathogens. One of these inhibitors is the plant flavonoid naringenin, which impairs the production of QS-regulated Pseudomonas aeruginosa virulence factors. In the present work, we analyze the molecular basis for such inhibition. Our data indicate that naringenin produces its effect by directly binding the QS regulator LasR, hence competing with its physiological activator, N-(3-oxo-dodecanoyl)-L-homoserine lactone (3OC12-HSL). The in vitro analysis of LasR binding to its cognate target DNA showed that the capacity of naringenin to outcompete 3OC12-HSL, when the latter is previously bound to LasR, is low. By using an E. coli LasR-based biosensor strain, which does not produce 3OC12-HSL, we determined that the inhibition of LasR is more efficient when naringenin binds to nascent LasR than when this regulator is already activated through 3OC12-HSL binding. According to these findings, at early exponential growth phase, when the amount of 3OC12-HSL is low, naringenin should proficiently inhibit the P. aeruginosa QS response, whereas at later stages of growth, once 3OC12-HSL concentration reaches a threshold enough for binding LasR, naringenin would not efficiently inhibit the QS response. To test this hypothesis, we analyze the potential effect of naringenin over the QS response by adding naringenin to P. aeruginosa cultures at either time zero (early inhibition) or at stationary growth phase (late inhibition). In early inhibitory conditions, naringenin inhibited the expression of QS-regulated genes, as well as the production of the QS-regulated virulence factors, pyocyanin and elastase. Nevertheless, in late inhibitory conditions, the P. aeruginosa QS response was not inhibited by naringenin. Therefore, this time-dependent inhibition may compromise the efficiency of this flavonoid, which will be effective just when used against bacterial populations presenting low cellular densities, and highlight the importance of searching for QS inhibitors whose mechanism of action does not depend on the QS status of the population.
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Affiliation(s)
- Sara Hernando-Amado
- Departamento de Biotecnología Microbiana, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Manuel Alcalde-Rico
- Departamento de Biotecnología Microbiana, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, Madrid, Spain
- Laboratorio de Genética e Inmunología Molecular, Instituto de Biología, Facultad de Ciencias, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
- Millennium Nucleus for Collaborative Research on Bacterial Resistance, Valparaíso, Chile
| | - Teresa Gil-Gil
- Departamento de Biotecnología Microbiana, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - José R. Valverde
- Servicio de Computación Científica, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - José L. Martínez
- Departamento de Biotecnología Microbiana, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, Madrid, Spain
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17
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Pseudomonas aeruginosa quorum-sensing metabolite induces host immune cell death through cell surface lipid domain dissolution. Nat Microbiol 2018; 4:97-111. [PMID: 30510173 DOI: 10.1038/s41564-018-0290-8] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Accepted: 10/10/2018] [Indexed: 01/02/2023]
Abstract
Bacterial quorum-sensing autoinducers are small chemicals released to control microbial community behaviours. N-(3-oxo-dodecanoyl) homoserine lactone, the autoinducer of the Pseudomonas aeruginosa LasI-LasR circuitry, triggers significant cell death in lymphocytes. We found that this molecule is incorporated into the mammalian plasma membrane and induces dissolution of eukaryotic lipid domains. This event expels tumour necrosis factor receptor 1 into the disordered lipid phase for its spontaneous trimerization without its ligand and drives caspase 3-caspase 8-mediated apoptosis. In vivo, P. aeruginosa releases N-(3-oxo-dodecanoyl) homoserine lactone to suppress host immunity for its own better survival; conversely, blockage of caspases strongly reduces the severity of the infection. This work reveals an unknown communication method between microorganisms and the mammalian host and suggests interventions of bacterial infections by intercepting quorum-sensing signalling.
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18
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Leggett HC, Cornwallis CK, Buckling A, West SA. Growth rate, transmission mode and virulence in human pathogens. Philos Trans R Soc Lond B Biol Sci 2017; 372:rstb.2016.0094. [PMID: 28289261 PMCID: PMC5352820 DOI: 10.1098/rstb.2016.0094] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/26/2016] [Indexed: 01/01/2023] Open
Abstract
The harm that pathogens cause to hosts during infection, termed virulence, varies across species from negligible to a high likelihood of rapid death. Classic theory for the evolution of virulence is based on a trade-off between pathogen growth, transmission and host survival, which predicts that higher within-host growth causes increased transmission and higher virulence. However, using data from 61 human pathogens, we found the opposite correlation to the expected positive correlation between pathogen growth rate and virulence. We found that (i) slower growing pathogens are significantly more virulent than faster growing pathogens, (ii) inhaled pathogens and pathogens that infect via skin wounds are significantly more virulent than pathogens that are ingested, but (iii) there is no correlation between symptoms of infection that aid transmission (such as diarrhoea and coughing) and virulence. Overall, our results emphasize how virulence can be influenced by mechanistic life-history details, especially transmission mode, that determine how parasites infect and exploit their hosts.This article is part of the themed issue 'Opening the black box: re-examining the ecology and evolution of parasite transmission'.
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Affiliation(s)
- Helen C Leggett
- Department of Genetics, University of Cambridge, Cambridge CB2 3EH, UK .,Department of Biosciences, University of Exeter, Cornwall Campus, Penryn TR10 9FE, UK
| | | | - Angus Buckling
- Department of Biosciences, University of Exeter, Cornwall Campus, Penryn TR10 9FE, UK
| | - Stuart A West
- Department of Zoology, University of Oxford, Oxford OX1 3PS, UK
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19
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Dahms HU, Dobretsov S. Antifouling Compounds from Marine Macroalgae. Mar Drugs 2017; 15:md15090265. [PMID: 28846625 PMCID: PMC5618404 DOI: 10.3390/md15090265] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Revised: 06/29/2017] [Accepted: 07/12/2017] [Indexed: 12/14/2022] Open
Abstract
Marine macroalgae produce a wide variety of biologically-active metabolites that have been developed into commercial products, such as antibiotics, immunosuppressive, anti-inflammatory, cytotoxic agents, and cosmetic products. Many marine algae remain clean over longer periods of time, suggesting their strong antifouling potential. Isolation of biogenic compounds and the determination of their structure could provide leads for the development of environmentally-friendly antifouling paints. Isolated substances with potent antifouling activity belong to fatty acids, lipopeptides, amides, alkaloids, lactones, steroids, terpenoids, and pyrroles. It is unclear as yet to what extent symbiotic microorganisms are involved in the synthesis of these compounds. Algal secondary metabolites have the potential to be produced commercially using genetic and metabolic engineering techniques. This review provides an overview of publications from 2010 to February 2017 about antifouling activity of green, brown, and red algae. Some researchers were focusing on antifouling compounds of brown macroalgae, while metabolites of green algae received less attention. Several studies tested antifouling activity against bacteria, microalgae and invertebrates, but in only a few studies was the quorum sensing inhibitory activity of marine macroalgae tested. Rarely, antifouling compounds from macroalgae were isolated and tested in an ecologically-relevant way.
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Affiliation(s)
- Hans Uwe Dahms
- Department of Biomedical Science and Environmental Biology, Kaohsiung Medical University, No. 100, Shin-Chuan 1st Road, Kaohsiung 80708, Taiwan.
- Department of Marine Biotechnology and Resources, National Sun Yat-sen University, No. 70, Lienhai Road, Kaohsiung 80424, Taiwan.
- Research Center for Environmental Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan.
| | - Sergey Dobretsov
- Center of Excellence in Marine Biotechnology, Sultan Qaboos University, Muscat 123, Oman.
- Department of Marine Science and Fisheries, College of Agricultural and Marine Sciences, Sultan Qaboos University, Muscat 123, Oman.
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20
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Characterization of N-Acyl Homoserine Lactones in Vibrio tasmaniensis LGP32 by a Biosensor-Based UHPLC-HRMS/MS Method. SENSORS 2017; 17:s17040906. [PMID: 28425948 PMCID: PMC5426830 DOI: 10.3390/s17040906] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Revised: 04/14/2017] [Accepted: 04/17/2017] [Indexed: 12/13/2022]
Abstract
Since the discovery of quorum sensing (QS) in the 1970s, many studies have demonstrated that Vibrio species coordinate activities such as biofilm formation, virulence, pathogenesis, and bioluminescence, through a large group of molecules called N-acyl homoserine lactones (AHLs). However, despite the extensive knowledge on the involved molecules and the biological processes controlled by QS in a few selected Vibrio strains, less is known about the overall diversity of AHLs produced by a broader range of environmental strains. To investigate the prevalence of QS capability of Vibrio environmental strains we analyzed 87 Vibrio spp. strains from the Banyuls Bacterial Culture Collection (WDCM911) for their ability to produce AHLs. This screening was based on three biosensors, which cover a large spectrum of AHLs, and revealed that only 9% of the screened isolates produced AHLs in the defined experimental conditions. Among these AHL-producing strains, Vibrio tasmaniensis LGP32 is a well-known pathogen of bivalves. We further analyzed the diversity of AHLs produced by this strain using a sensitive bioguided UHPLC-HRMS/MS approach (Ultra-High-Performance Liquid Chromatography followed by High-Resolution tandem Mass Spectrometry) and we identified C10-HSL, OH-C12-HSL, oxo-C12-HSL and C14:1-HSL as QS molecules. This is the first report that documents the production of AHL by Vibrio tasmaniensis LGP32.
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21
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Quorum sensing by farnesol revisited. Curr Genet 2017; 63:791-797. [DOI: 10.1007/s00294-017-0683-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Revised: 02/01/2017] [Accepted: 02/07/2017] [Indexed: 12/18/2022]
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22
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Gibbs KA, Shen A. Editorial: Signals to sociality: how microbial communication fashions communities. FEMS Microbiol Rev 2016; 40:795-797. [PMID: 28201572 DOI: 10.1093/femsre/fuw039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Karine A Gibbs
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA, USA
| | - Aimee Shen
- Department of Molecular Biology and Microbiology, Tufts Medical School, Boston, USA
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23
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Palmer AG, Mukherjee A, Stacy DM, Lazar S, Ané JM, Blackwell HE. Interkingdom Responses to Bacterial Quorum Sensing Signals Regulate Frequency and Rate of Nodulation in Legume-Rhizobia Symbiosis. Chembiochem 2016; 17:2199-2205. [DOI: 10.1002/cbic.201600373] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2016] [Indexed: 12/26/2022]
Affiliation(s)
- Andrew G. Palmer
- Department of Biological Sciences; Florida Institute of Technology; 150 West University Melbourne FL 32904 USA
| | - Arijit Mukherjee
- Department of Biology; University of Central Arkansas; 201 Donaghey Conway AK 72035 USA
| | - Danielle M. Stacy
- Department of Chemistry; University of Wisconsin-Madison; 1101 University Avenue Madison WI 53706 USA
| | - Stephen Lazar
- Department of Biological Sciences; Florida Institute of Technology; 150 West University Melbourne FL 32904 USA
| | - Jean-Michel Ané
- Department of Agronomy; University of Wisconsin-Madison; 1575 Linden Drive Madison WI 53706 USA
- Department of Bacteriology; University of Wisconsin-Madison; 1550 Linden Drive Madison WI 53706 USA
| | - Helen E. Blackwell
- Department of Chemistry; University of Wisconsin-Madison; 1101 University Avenue Madison WI 53706 USA
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24
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Silva LN, Zimmer KR, Macedo AJ, Trentin DS. Plant Natural Products Targeting Bacterial Virulence Factors. Chem Rev 2016; 116:9162-236. [PMID: 27437994 DOI: 10.1021/acs.chemrev.6b00184] [Citation(s) in RCA: 263] [Impact Index Per Article: 32.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Decreased antimicrobial efficiency has become a global public health issue. The paucity of new antibacterial drugs is evident, and the arsenal against infectious diseases needs to be improved urgently. The selection of plants as a source of prototype compounds is appropriate, since plant species naturally produce a wide range of secondary metabolites that act as a chemical line of defense against microorganisms in the environment. Although traditional approaches to combat microbial infections remain effective, targeting microbial virulence rather than survival seems to be an exciting strategy, since the modulation of virulence factors might lead to a milder evolutionary pressure for the development of resistance. Additionally, anti-infective chemotherapies may be successfully achieved by combining antivirulence and conventional antimicrobials, extending the lifespan of these drugs. This review presents an updated discussion of natural compounds isolated from plants with chemically characterized structures and activity against the major bacterial virulence factors: quorum sensing, bacterial biofilms, bacterial motility, bacterial toxins, bacterial pigments, bacterial enzymes, and bacterial surfactants. Moreover, a critical analysis of the most promising virulence factors is presented, highlighting their potential as targets to attenuate bacterial virulence. The ongoing progress in the field of antivirulence therapy may therefore help to translate this promising concept into real intervention strategies in clinical areas.
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Affiliation(s)
- Laura Nunes Silva
- Faculdade de Farmácia, Universidade Federal do Rio Grande do Sul , Porto Alegre, Rio Grande do Sul 90610-000, Brazil.,Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul , Porto Alegre, Rio Grande do Sul 91501-970, Brazil
| | - Karine Rigon Zimmer
- Departamento de Ciências Básicas da Saúde, Universidade Federal de Ciências da Saúde de Porto Alegre , Porto Alegre, Rio Grande do Sul 90050-170, Brazil
| | - Alexandre José Macedo
- Faculdade de Farmácia, Universidade Federal do Rio Grande do Sul , Porto Alegre, Rio Grande do Sul 90610-000, Brazil.,Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul , Porto Alegre, Rio Grande do Sul 91501-970, Brazil.,Instituto Nacional do Semiárido , Campina Grande, Paraı́ba 58429-970, Brazil
| | - Danielle Silva Trentin
- Faculdade de Farmácia, Universidade Federal do Rio Grande do Sul , Porto Alegre, Rio Grande do Sul 90610-000, Brazil.,Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul , Porto Alegre, Rio Grande do Sul 91501-970, Brazil
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25
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Hawver LA, Jung SA, Ng WL. Specificity and complexity in bacterial quorum-sensing systems. FEMS Microbiol Rev 2016; 40:738-52. [PMID: 27354348 PMCID: PMC5007282 DOI: 10.1093/femsre/fuw014] [Citation(s) in RCA: 162] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/18/2016] [Indexed: 12/15/2022] Open
Abstract
Quorum sensing (QS) is a microbial cell-to-cell communication process that relies on the production and detection of chemical signals called autoinducers (AIs) to monitor cell density and species complexity in the population. QS allows bacteria to behave as a cohesive group and coordinate collective behaviors. While most QS receptors display high specificity to their AI ligands, others are quite promiscuous in signal detection. How do specific QS receptors respond to their cognate signals with high fidelity? Why do some receptors maintain low signal recognition specificity? In addition, many QS systems are composed of multiple intersecting signaling pathways: what are the benefits of preserving such a complex signaling network when a simple linear ‘one-to-one’ regulatory pathway seems sufficient to monitor cell density? Here, we will discuss different molecular mechanisms employed by various QS systems that ensure productive and specific QS responses. Moreover, the network architectures of some well-characterized QS circuits will be reviewed to understand how the wiring of different regulatory components achieves different biological goals. This review focuses on the specificity and complexity of quorum-sensing circuits in both Gram-negative and Gram-positive bacterial species.
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Affiliation(s)
- Lisa A Hawver
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, MA 02111, USA
| | - Sarah A Jung
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, MA 02111, USA Program in Molecular Microbiology, Sackler School of Graduate Biomedical Sciences, Tufts University, Boston, MA 02111, USA
| | - Wai-Leung Ng
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, MA 02111, USA Program in Molecular Microbiology, Sackler School of Graduate Biomedical Sciences, Tufts University, Boston, MA 02111, USA
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26
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Soares dos Santos A, Pereira Jr N, Freire DM. Strategies for improved rhamnolipid production by Pseudomonas aeruginosa PA1. PeerJ 2016; 4:e2078. [PMID: 27257553 PMCID: PMC4888285 DOI: 10.7717/peerj.2078] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Accepted: 05/03/2016] [Indexed: 11/20/2022] Open
Abstract
Rhamnolipids are biosurfactants with potential for diversified industrial and environmental uses. The present study evaluated three strategies for increasing the production of rhamnolipid-type biosurfactants produced by Pseudomonas aeruginosa strain PA1. The influence of pH, the addition of P. aeruginosa spent culture medium and the use of a fed-batch process were examined. The culture medium adjusted to pH 7.0 was the most productive. Furthermore, the pH of the culture medium had a measurable effect on the ratio of synthesized mono- and dirhamnolipids. At pH values below 7.3, the proportion of monorhamnolipids decreased from 45 to 24%. The recycling of 20% of the spent culture medium in where P. aeruginosa was grown up to the later stationary phase was responsible for a 100% increase in rhamnolipid volumetric productivity in the new culture medium. Finally, the use of fed-batch operation under conditions of limited nitrogen resulted in a 3.8-fold increase in the amount of rhamnolipids produced (2.9 g L(-1)-10.9 g L(-1)). These results offer promising pathways for the optimization of processes for the production of rhamnolipids.
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Affiliation(s)
- Alexandre Soares dos Santos
- Department of Basic Science/Faculty of Biological Science and Health, Universidade Federal dos Vales do Jequitinhonha e Mucuri, Diamantina, Minas Gerais, Brazil
| | - Nei Pereira Jr
- Department of Biochemical Engineering/School of Chemistry, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Denise M.G. Freire
- Department of Biochemistry/Institute of Chemistry, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
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27
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Fungal dimorphism in the entomopathogenic fungus Metarhizium rileyi: Detection of an in vivo quorum-sensing system. J Invertebr Pathol 2016; 136:100-8. [DOI: 10.1016/j.jip.2016.03.013] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Revised: 03/21/2016] [Accepted: 03/22/2016] [Indexed: 11/21/2022]
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28
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Effects of an inducible aiiA gene on disease resistance in Eucalyptus urophylla × Eucalyptus grandis. Transgenic Res 2016; 25:441-52. [DOI: 10.1007/s11248-016-9940-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Accepted: 02/17/2016] [Indexed: 10/22/2022]
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29
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Impairment of Pseudomonas aeruginosa Biofilm Resistance to Antibiotics by Combining the Drugs with a New Quorum-Sensing Inhibitor. Antimicrob Agents Chemother 2015; 60:1676-86. [PMID: 26711774 DOI: 10.1128/aac.02533-15] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Accepted: 12/19/2015] [Indexed: 01/29/2023] Open
Abstract
Pseudomonas aeruginosa plays an important role in chronic lung infections among patients with cystic fibrosis (CF) through its ability to form antibiotic-resistant biofilms. In P. aeruginosa, biofilm development and the production of several virulence factors are mainly regulated by the rhl and las quorum-sensing (QS) systems, which are controlled by two N-acyl-homoserine lactone signal molecules. In a previous study, we discovered an original QS inhibitor, N-(2-pyrimidyl)butanamide, called C11, based on the structure of C4-homoserine lactone, and found that it is able to significantly inhibit P. aeruginosa biofilm formation. However, recent data indicate that P. aeruginosa grows under anaerobic conditions and forms biofilms in the lungs of CF patients that are denser and more robust than those formed under aerobic conditions. Our confocal microscopy observations of P. aeruginosa biofilms developed under aerobic and anaerobic conditions confirmed that the biofilms formed under these two conditions have radically different architectures. C11 showed significant dose-dependent antibiofilm activity on biofilms grown under both aerobic and anaerobic conditions, with a greater inhibitory effect being seen under conditions of anaerobiosis. Gene expression analyses performed by quantitative reverse transcriptase PCR showed that C11 led to the significant downregulation of rhl QS regulatory genes but also to the downregulation of both las QS regulatory genes and QS system-regulated virulence genes, rhlA and lasB. Furthermore, the activity of C11 in combination with antibiotics against P. aeruginosa biofilms was tested, and synergistic antibiofilm activity between C11 and ciprofloxacin, tobramycin, and colistin was obtained under both aerobic and anaerobic conditions. This study demonstrates that C11 may increase the efficacy of treatments for P. aeruginosa infections by increasing the susceptibility of biofilms to antibiotics and by attenuating the pathogenicity of the bacterium.
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30
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Strasser MK, Feigelman J, Theis FJ, Marr C. Inference of spatiotemporal effects on cellular state transitions from time-lapse microscopy. BMC SYSTEMS BIOLOGY 2015; 9:61. [PMID: 26391569 PMCID: PMC4578671 DOI: 10.1186/s12918-015-0208-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Accepted: 09/08/2015] [Indexed: 11/10/2022]
Abstract
BACKGROUND Time-lapse microscopy allows to monitor cell state transitions in a spatiotemporal context. Combined with single cell tracking and appropriate cell state markers, transition events can be observed within the genealogical relationship of a proliferating population. However, to infer the correlations between the spatiotemporal context and cell state transitions, statistical analysis with an appropriately large number of samples is required. RESULTS Here, we present a method to infer spatiotemporal features predictive of the state transition events observed in time-lapse microscopy data. We first formulate a generative model, simulate different scenarios, such as time-dependent or local cell density-dependent transitions, and illustrate how to estimate univariate transition rates. Second, we formulate the problem in a machine-learning language using regularized linear models. This allows for a multivariate analysis and to disentangle indirect dependencies via feature selection. We find that our method can accurately recover the relevant features and reconstruct the underlying interaction kernels if a critical number of samples is available. Finally, we explicitly use the tree structure of the data to validate if the estimated model is sufficient to explain correlated transition events of sister cells. CONCLUSIONS Using synthetic cellular genealogies, we prove that our method is able to correctly identify features predictive of state transitions and we moreover validate the chosen model. Our approach allows to estimate the number of cellular genealogies required for the proposed spatiotemporal statistical analysis, and we thus provide an important tool for the experimental design of challenging single cell time-lapse microscopy assays.
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Affiliation(s)
- Michael K Strasser
- Institute of Computational Biology, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter Landstr. 1, Neuherberg, 85764, Germany.
| | - Justin Feigelman
- Institute of Computational Biology, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter Landstr. 1, Neuherberg, 85764, Germany.
- Department of Mathematics, Technische Universität München, Boltzmannstr. 3, Garching, 85747, Germany.
| | - Fabian J Theis
- Institute of Computational Biology, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter Landstr. 1, Neuherberg, 85764, Germany.
- Department of Mathematics, Technische Universität München, Boltzmannstr. 3, Garching, 85747, Germany.
| | - Carsten Marr
- Institute of Computational Biology, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter Landstr. 1, Neuherberg, 85764, Germany.
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Blanchard AE, Lu T. Bacterial social interactions drive the emergence of differential spatial colony structures. BMC SYSTEMS BIOLOGY 2015; 9:59. [PMID: 26377684 PMCID: PMC4573487 DOI: 10.1186/s12918-015-0188-5] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Accepted: 07/08/2015] [Indexed: 12/25/2022]
Abstract
Background Social interactions have been increasingly recognized as one of the major factors that contribute to the dynamics and function of bacterial communities. To understand their functional roles and enable the design of robust synthetic consortia, one fundamental step is to determine the relationship between the social interactions of individuals and the spatiotemporal structures of communities. Results We present a systematic computational survey on this relationship for two-species communities by developing and utilizing a hybrid computational framework that combines discrete element techniques with reaction-diffusion equations. We found that deleterious interactions cause an increased variance in relative abundance, a drastic decrease in surviving lineages, and a rough expanding front. In contrast, beneficial interactions contribute to a reduced variance in relative abundance, an enhancement in lineage number, and a smooth expanding front. We also found that mutualism promotes spatial homogeneity and population robustness while competition increases spatial segregation and population fluctuations. To examine the generality of these findings, a large set of initial conditions with varying density and species abundance was tested and analyzed. In addition, a simplified mathematical model was developed to provide an analytical interpretation of the findings. Conclusions This work advances our fundamental understanding of bacterial social interactions and population structures and, simultaneously, benefits synthetic biology for facilitated engineering of artificial microbial consortia. Electronic supplementary material The online version of this article (doi:10.1186/s12918-015-0188-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Andrew E Blanchard
- Department of Physics, University of Illinois at Urbana-Champaign, 1110 West Green Street, Urbana, 61801, USA.
| | - Ting Lu
- Department of Physics, University of Illinois at Urbana-Champaign, 1110 West Green Street, Urbana, 61801, USA. .,Department of Bioengineering, University of Illinois at Urbana-Champaign, 1304 West Springfield Avenue, Urbana, 61801, USA. .,Institute for Genomic Biology, University of Illinois at Urbana-Champaign, 1206 West Gregory Drive, Urbana, 61801, USA.
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Zhao J, Chen M, Quan CS, Fan SD. Mechanisms of quorum sensing and strategies for quorum sensing disruption in aquaculture pathogens. JOURNAL OF FISH DISEASES 2015; 38:771-786. [PMID: 25219871 DOI: 10.1111/jfd.12299] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2014] [Revised: 07/02/2014] [Accepted: 07/07/2014] [Indexed: 06/03/2023]
Abstract
In many countries, infectious diseases are a considerable threat to aquaculture. The pathogenicity of micro-organisms that infect aquaculture systems is closely related to the release of virulence factors and the formation of biofilms, both of which are regulated by quorum sensing (QS). Thus, QS disruption is a potential strategy for preventing disease in aquaculture systems. QS inhibitors (QSIs) not only inhibit the expression of virulence-associated genes but also attenuate the virulence of aquaculture pathogens. In this review, we discuss QS systems in important aquaculture pathogens and focus on the relationship between QS mechanisms and bacterial virulence in aquaculture. We further elucidate QS disruption strategies for targeting aquaculture pathogens. Four main types of QSIs that target aquaculture pathogens are discussed based on their mechanisms of action.
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Affiliation(s)
- J Zhao
- Key Laboratory of Biochemical Engineering State Ethnic Affairs Commission-Ministry of Education, Dalian Nationalities University, Dalian, China
- College of Life Science, Dalian Nationalities University, Dalian, China
| | - M Chen
- College of Bioengineering, Dalian Polytechnic University, Dalian, China
| | - C S Quan
- Key Laboratory of Biochemical Engineering State Ethnic Affairs Commission-Ministry of Education, Dalian Nationalities University, Dalian, China
- College of Life Science, Dalian Nationalities University, Dalian, China
| | - S D Fan
- Key Laboratory of Biochemical Engineering State Ethnic Affairs Commission-Ministry of Education, Dalian Nationalities University, Dalian, China
- College of Life Science, Dalian Nationalities University, Dalian, China
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Mukherji R, Prabhune A. A new class of bacterial quorum sensing antagonists: glycomonoterpenols synthesized using linalool and alpha terpineol. World J Microbiol Biotechnol 2015; 31:841-9. [DOI: 10.1007/s11274-015-1822-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Accepted: 02/07/2015] [Indexed: 11/29/2022]
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Popat R, Cornforth DM, McNally L, Brown SP. Collective sensing and collective responses in quorum-sensing bacteria. J R Soc Interface 2015; 12:20140882. [PMID: 25505130 PMCID: PMC4305403 DOI: 10.1098/rsif.2014.0882] [Citation(s) in RCA: 84] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Accepted: 11/12/2014] [Indexed: 11/21/2022] Open
Abstract
Bacteria often face fluctuating environments, and in response many species have evolved complex decision-making mechanisms to match their behaviour to the prevailing conditions. Some environmental cues provide direct and reliable information (such as nutrient concentrations) and can be responded to individually. Other environmental parameters are harder to infer and require a collective mechanism of sensing. In addition, some environmental challenges are best faced by a group of cells rather than an individual. In this review, we discuss how bacteria sense and overcome environmental challenges as a group using collective mechanisms of sensing, known as 'quorum sensing' (QS). QS is characterized by the release and detection of small molecules, potentially allowing individuals to infer environmental parameters such as density and mass transfer. While a great deal of the molecular mechanisms of QS have been described, there is still controversy over its functional role. We discuss what QS senses and how, what it controls and why, and how social dilemmas shape its evolution. Finally, there is a growing focus on the use of QS inhibitors as antibacterial chemotherapy. We discuss the claim that such a strategy could overcome the evolution of resistance. By linking existing theoretical approaches to data, we hope this review will spur greater collaboration between experimental and theoretical researchers.
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Affiliation(s)
- R Popat
- Centre for Immunity, Infection and Evolution, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3JT, UK
| | - D M Cornforth
- Centre for Immunity, Infection and Evolution, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3JT, UK Molecular Biosciences, University of Texas at Austin, 2500 Speedway NMS 3.254, Austin, TX 78712, USA
| | - L McNally
- Centre for Immunity, Infection and Evolution, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3JT, UK
| | - S P Brown
- Centre for Immunity, Infection and Evolution, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3JT, UK
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Vasavi HS, Arun AB, Rekha PD. Anti-quorum sensing potential of Adenanthera pavonina. Pharmacognosy Res 2015; 7:105-9. [PMID: 25598643 PMCID: PMC4285638 DOI: 10.4103/0974-8490.147220] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Revised: 04/26/2014] [Accepted: 12/17/2014] [Indexed: 11/26/2022] Open
Abstract
Background: Quorum sensing (QS) in Pseudomonas aeruginosa plays a key role in virulence factor production, biofilm formation and antimicrobial resistance. Because of emerging antimicrobial resistance in P. aeruginosa, there is a need to find an alternate nonantibiotic agent for the control of infections caused by this organism. Objective: To evaluate anti-QS activity of Adenanthera pavonina L., a medicinal plant used in traditional medicine. Materials and Methods: Preliminary screening for anti-QS activity of ethanol extract of A. pavonina was carried out using Chromobacterium violaceum CV026 biosensor strain and inhibition of QS-regulated violacein production was quantified using C. violaceum ATCC12472. Bioassay guided fractionation of ethanol extract resulted in ethyl acetate fraction (AEF) with strong anti-QS activity and AEF was evaluated for inhibition of QS-regulated pyocyanin production, proteolytic, elastolytic activity, swarming motility and biofilm formation in P. aeruginosa PAO1. Results: AEF, at 0.5 mg/ml, inhibited pyocyanin production completely and at 1 mg/ml of AEF, complete inhibition of proteolytic and elastolytic activities were observed. However, viability of P. aeruginosa PAO1 was not affected at the tested concentrations of AEF as observed by cell count. Swarming motility was inhibited at the concentration of 0.1 mg/ml of AEF. Thin layer chromatography and biosensor overlay of AEF showed violacein inhibition zone at Rf value 0.63. Conclusion: From the results of this study, it can be concluded that A. pavonina extracts can be used as effective anti-QS agents.
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Affiliation(s)
| | | | - Punchappady-Devasya Rekha
- Yenepoya Research Center, Yenepoya University, University Road, Deralakatte, Mangalore, Karnataka, India
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Chourasiya SS, Kathuria D, Singh S, Sonawane VC, Chakraborti AK, Bharatam PV. Design, synthesis and biological evaluation of novel unsymmetrical azines as quorum sensing inhibitors. RSC Adv 2015. [DOI: 10.1039/c5ra12925g] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
In this report, novel unsymmetrical azines have been designed and synthesised by using one pot approach. Further, they were evaluated as quorum sensing inhibitors.
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Affiliation(s)
- Sumit S. Chourasiya
- Department of Medicinal Chemistry
- National Institute of Pharmaceutical Education and Research (NIPER)
- India
| | - Deepika Kathuria
- Department of Medicinal Chemistry
- National Institute of Pharmaceutical Education and Research (NIPER)
- India
| | - Shaminder Singh
- Bio-Chemical Engineering Research and Process Development Centre (BERPDC)
- Institute of Microbial Technology (IMTECH)
- India
| | - Vijay C. Sonawane
- Bio-Chemical Engineering Research and Process Development Centre (BERPDC)
- Institute of Microbial Technology (IMTECH)
- India
| | - Asit K. Chakraborti
- Department of Medicinal Chemistry
- National Institute of Pharmaceutical Education and Research (NIPER)
- India
| | - Prasad V. Bharatam
- Department of Medicinal Chemistry
- National Institute of Pharmaceutical Education and Research (NIPER)
- India
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37
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Busetti A, Shaw G, Megaw J, Gorman SP, Maggs CA, Gilmore BF. Marine-derived quorum-sensing inhibitory activities enhance the antibacterial efficacy of tobramycin against Pseudomonas aeruginosa. Mar Drugs 2014; 13:1-28. [PMID: 25546516 PMCID: PMC4306922 DOI: 10.3390/md13010001] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2014] [Accepted: 12/15/2014] [Indexed: 01/02/2023] Open
Abstract
Bacterial epiphytes isolated from marine eukaryotes were screened for the production of quorum sensing inhibitory compounds (QSIs). Marine isolate KS8, identified as a Pseudoalteromonas sp., was found to display strong quorum sensing inhibitory (QSI) activity against acyl homoserine lactone (AHL)-based reporter strains Chromobacterium violaceum ATCC 12472 and CV026. KS8 supernatant significantly reduced biofilm biomass during biofilm formation (-63%) and in pre-established, mature P. aeruginosa PAO1 biofilms (-33%). KS8 supernatant also caused a 0.97-log reduction (-89%) and a 2-log reduction (-99%) in PAO1 biofilm viable counts in the biofilm formation assay and the biofilm eradication assay respectively. The crude organic extract of KS8 had a minimum inhibitory concentration (MIC) of 2 mg/mL against PAO1 but no minimum bactericidal concentration (MBC) was observed over the concentration range tested (MBC > 16 mg/mL). Sub-MIC concentrations (1 mg/mL) of KS8 crude organic extract significantly reduced the quorum sensing (QS)-dependent production of both pyoverdin and pyocyanin in P. aeruginosa PAO1 without affecting growth. A combinatorial approach using tobramycin and the crude organic extract at 1 mg/mL against planktonic P. aeruginosa PAO1 was found to increase the efficacy of tobramycin ten-fold, decreasing the MIC from 0.75 to 0.075 µg/mL. These data support the validity of approaches combining conventional antibiotic therapy with non-antibiotic compounds to improve the efficacy of current treatments.
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Affiliation(s)
- Alessandro Busetti
- School of Pharmacy, Queen's University Belfast, 97 Lisburn Rd, Belfast BT9 7BL, UK.
| | - George Shaw
- School of Pharmacy, Queen's University Belfast, 97 Lisburn Rd, Belfast BT9 7BL, UK.
| | - Julianne Megaw
- School of Pharmacy, Queen's University Belfast, 97 Lisburn Rd, Belfast BT9 7BL, UK.
| | - Sean P Gorman
- School of Pharmacy, Queen's University Belfast, 97 Lisburn Rd, Belfast BT9 7BL, UK.
| | - Christine A Maggs
- School of Biological Sciences, Medical Biology Center, 97 Lisburn Road, Belfast BT9 7BL, UK.
| | - Brendan F Gilmore
- School of Pharmacy, Queen's University Belfast, 97 Lisburn Rd, Belfast BT9 7BL, UK.
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38
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Tandem mass spectrometry detection of quorum sensing activity in multidrug resistant clinical isolate Acinetobacter baumannii. ScientificWorldJournal 2014; 2014:891041. [PMID: 25101326 PMCID: PMC4101932 DOI: 10.1155/2014/891041] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2014] [Revised: 06/01/2014] [Accepted: 06/02/2014] [Indexed: 01/27/2023] Open
Abstract
Many Proteobacteria communicate via production followed by response of quorum sensing molecules, namely, N-acyl homoserine lactones (AHLs). These molecules consist of a lactone moiety with N-acyl side chain with various chain lengths and degrees of saturation at C-3 position. AHL-dependent QS is often associated with regulation of diverse bacterial phenotypes including the expression of virulence factors. With the use of biosensor and high resolution liquid chromatography tandem mass spectrometry, the AHL production of clinical isolate A. baumannii 4KT was studied. Production of short chain AHL, namely, N-hexanoyl-homoserine lactone (C6-HSL) and N-octanoyl-homoserine lactone (C8-HSL), was detected.
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39
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Al-Maleki AR, Mariappan V, Vellasamy KM, Shankar EM, Tay ST, Vadivelu J. Enhanced intracellular survival and epithelial cell adherence abilities of Burkholderia pseudomallei morphotypes are dependent on differential expression of virulence-associated proteins during mid-logarithmic growth phase. J Proteomics 2014; 106:205-20. [DOI: 10.1016/j.jprot.2014.04.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2013] [Revised: 03/21/2014] [Accepted: 04/02/2014] [Indexed: 10/25/2022]
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40
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Mukherji R, Samanta A, Illathvalappil R, Chowdhury S, Prabhune A, Devi RN. Selective imaging of quorum sensing receptors in bacteria using fluorescent Au nanocluster probes surface functionalized with signal molecules. ACS APPLIED MATERIALS & INTERFACES 2013; 5:13076-81. [PMID: 24266726 DOI: 10.1021/am404093m] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Fluorescent ultrasmall gold clusters decorated with bacterial quorum sensing signal molecules, acyl homoserine lactone, are synthesized. These fluorescent probes are found to have emission in the near-infrared spectral region advantageous for bioimaging. Imaging studies using different strains of bacteria with and without acyl homoserine lactone receptors with the aid of confocal microscopy have shown that the probe interacts preferentially with cells possessing these receptors. This indicates that, with appropriate surface functionalization, the Au clusters can be used for receptor specific detection with enhanced selectivity.
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Affiliation(s)
- Ruchira Mukherji
- Biochemistry Division, CSIR-National Chemical Laboratory , Dr. Homi Bhabha Road, Pune 411008, India
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41
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van Baalen M. Biological information: why we need a good measure and the challenges ahead. Interface Focus 2013; 3:20130030. [PMID: 24516717 PMCID: PMC3915847 DOI: 10.1098/rsfs.2013.0030] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Evolution can be characterized as a process that shapes and maintains information across generations. It is also widely acknowledged that information may play a pivotal role in many other ecological processes. Most of the ecologically relevant information (and some important evolutionary information too) is of a very subjective and analogue kind: individuals use cues that may carry information useful only to them but not to others. This is a problem because most information theory has been developed for objective and discrete information. Can information theory be extended to this theory to incorporate multiple forms of information, each with its own (physical) carriers and dynamics? Here, I will not review all the possible roles that information can play, but rather what conditions an appropriate theory should satisfy. The most promising starting point is provided by entropy measures of conditional probabilities (using the so-called Kullback-Leibler divergence), allowing an assessment of how acquiring information can lead to an increase in fitness. It is irrelevant (to a certain extent) where the information comes from-genes, experience or culture-but it is important to realize that information is not merely subjective but its value should be evaluated in fitness terms, and it is here that evolutionary theory has an enormous potential. A number of important stumbling points remain, however; namely, the identification of whose fitness it concerns and what role the spatio-temporal dynamics plays (which is tightly linked to the nature of the physical carriers of the information and the processes that impact on it).
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Affiliation(s)
- Minus van Baalen
- CNRS-UPMC-ENS UMR 7625 Ecologie & Evolution, Université Pierre et Marie Curie, Bat A 7ème Etage, CC 237, Paris 75252, France
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42
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Ransome E, Munn CB, Halliday N, Cámara M, Tait K. Diverse profiles ofN-acyl-homoserine lactone molecules found in cnidarians. FEMS Microbiol Ecol 2013; 87:315-29. [DOI: 10.1111/1574-6941.12226] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2013] [Revised: 09/06/2013] [Accepted: 09/15/2013] [Indexed: 12/11/2022] Open
Affiliation(s)
- Emma Ransome
- Plymouth Marine Laboratory; Plymouth Devon UK
- School of Marine Science and Engineering; Plymouth University; Plymouth UK
| | - Colin B. Munn
- School of Marine Science and Engineering; Plymouth University; Plymouth UK
| | - Nigel Halliday
- School of Molecular Medical Sciences; Centre for Biomolecular Sciences; University of Nottingham; Nottingham UK
| | - Miguel Cámara
- School of Molecular Medical Sciences; Centre for Biomolecular Sciences; University of Nottingham; Nottingham UK
| | - Karen Tait
- Plymouth Marine Laboratory; Plymouth Devon UK
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Weidel E, de Jong JC, Brengel C, Storz MP, Braunshausen A, Negri M, Plaza A, Steinbach A, Müller R, Hartmann RW. Structure optimization of 2-benzamidobenzoic acids as PqsD inhibitors for Pseudomonas aeruginosa infections and elucidation of binding mode by SPR, STD NMR, and molecular docking. J Med Chem 2013; 56:6146-55. [PMID: 23834469 DOI: 10.1021/jm4006302] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Pseudomonas aeruginosa employs a characteristic pqs quorum sensing (QS) system that functions via the signal molecules PQS and its precursor HHQ. They control the production of a number of virulence factors and biofilm formation. Recently, we have shown that sulfonamide substituted 2-benzamidobenzoic acids, which are known FabH inhibitors, are also able to inhibit PqsD, the enzyme catalyzing the last and key step in the biosynthesis of HHQ. Here, we describe the further optimization and characterization of this class of compounds as PqsD inhibitors. Structural modifications showed that both the carboxylic acid ortho to the amide and 3'-sulfonamide are essential for binding. Introduction of substituents in the anthranilic part of the molecule resulted in compounds with IC50 values in the low micromolar range. Binding mode investigations by SPR with wild-type and mutated PqsD revealed that this compound class does not bind into the active center of PqsD but in the ACoA channel, preventing the substrate from accessing the active site. This binding mode was further confirmed by docking studies and STD NMR.
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Affiliation(s)
- Elisabeth Weidel
- Helmholtz-Institute for Pharmaceutical Research Saarland (HIPS) , Department of Drug Design and Optimization, Campus C2.3, 66123 Saarbrücken, Germany
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44
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Fones H, Preston GM. The impact of transition metals on bacterial plant disease. FEMS Microbiol Rev 2013; 37:495-519. [DOI: 10.1111/1574-6976.12004] [Citation(s) in RCA: 81] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2012] [Revised: 09/05/2012] [Accepted: 09/14/2012] [Indexed: 12/24/2022] Open
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Erken M, Lutz C, McDougald D. The rise of pathogens: predation as a factor driving the evolution of human pathogens in the environment. MICROBIAL ECOLOGY 2013; 65:860-8. [PMID: 23354181 PMCID: PMC3637895 DOI: 10.1007/s00248-013-0189-0] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2012] [Accepted: 01/14/2013] [Indexed: 05/08/2023]
Abstract
Bacteria in the environment must survive predation from bacteriophage, heterotrophic protists, and predatory bacteria. This selective pressure has resulted in the evolution of a variety of defense mechanisms, which can also function as virulence factors. Here we discuss the potential dual function of some of the mechanisms, which protect against heterotrophic protists, and how predation pressure leads to the evolution of pathogenicity. This is in accordance with the coincidental evolution hypothesis, which suggests that virulence factors arose as a response to other selective pressures, for example, predation rather than for virulence per se. In this review we discuss some of those environmental factors that may be associated with the rise of pathogens in the marine environment. In particular, we will discuss the role of heterotrophic protists in the evolution of virulence factors in marine bacteria. Finally, we will discuss the implications for expansion of current pathogens and emergence of new pathogens.
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Affiliation(s)
- Martina Erken
- Centre for Marine Bio-Innovation, School of Biotechnology and Biomolecular Science, University of New South Wales, Sydney, New South Wales 2052 Australia
| | - Carla Lutz
- Centre for Marine Bio-Innovation, School of Biotechnology and Biomolecular Science, University of New South Wales, Sydney, New South Wales 2052 Australia
| | - Diane McDougald
- Centre for Marine Bio-Innovation, School of Biotechnology and Biomolecular Science, University of New South Wales, Sydney, New South Wales 2052 Australia
- Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, School of Biological Sciences, Nanyang Technological University, Nanyang Avenue, Singapore, 637551 Singapore
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Abstract
Many pathogenic bacteria use quorum sensing (QS) systems to regulate the expression of virulence genes in a density-dependent manner. In one widespread QS paradigm the enzyme LuxI generates a small diffusible molecule of the acyl-homoserine lactone (AHL) family; high cell densities lead to high AHL levels; AHL binds the transcription factor LuxR, triggering it to activate gene expression at a virulence promoter. The emergence of antibiotic resistance has generated interest in alternative anti-microbial therapies that target QS. Inhibitors of LuxI and LuxR have been developed and tested in vivo, and can act at various levels: inhibiting the synthesis of AHL by LuxI, competitively or non-competitively inhibiting LuxR, or increasing the turnover of LuxI, LuxR, or AHL. Here use an experimentally validated computational model of LuxI/LuxR QS to study the effects of using inhibitors individually and in combination. The model includes the effect of transcriptional feedback, which generates highly non-linear responses as inhibitor levels are increased. For the ubiquitous LuxI-feedback virulence systems, inhibitors of LuxI are more effective than those of LuxR when used individually. Paradoxically, we find that LuxR competitive inhibitors, either individually or in combination with other inhibitors, can sometimes increase virulence by weakly activating LuxR. For both LuxI-feedback and LuxR-feedback systems, a combination of LuxR non-competitive inhibitors and LuxI inhibitors act multiplicatively over a broad parameter range. In our analysis, this final strategy emerges as the only robust therapeutic option.
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Affiliation(s)
- Rajat Anand
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, UAS/GKVK Campus, Bangalore, India
| | - Navneet Rai
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, UAS/GKVK Campus, Bangalore, India
- Department of BioSciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai, India
| | - Mukund Thattai
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, UAS/GKVK Campus, Bangalore, India
- * E-mail:
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Norizan SNM, Yin WF, Chan KG. Caffeine as a potential quorum sensing inhibitor. SENSORS 2013; 13:5117-29. [PMID: 23598500 PMCID: PMC3673129 DOI: 10.3390/s130405117] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/25/2013] [Revised: 04/10/2013] [Accepted: 04/16/2013] [Indexed: 12/31/2022]
Abstract
Quorum sensing enables bacteria to control the gene expression in response to the cell density. It regulates a variety of bacterial physiological functions such as biofilm formation, bioluminescence, virulence factors and swarming which has been shown contribute to bacterial pathogenesis. The use of quorum sensing inhibitor would be of particular interest in treating bacterial pathogenicity and infections. In this work, we have tested caffeine as quorum sensing inhibitor by using Chromobacterium violaceum CV026 as a biosensor. We verified that caffeine did not degrade the N-acyl homoserine lactones tested. In this work, it is shown that caffeine could inhibit N-acyl homoserine lactone production and swarming of a human opportunistic pathogen, namely Pseudomonas aeruginosa PA01. To the best of our knowledge, this is the first documentation providing evidence on the presence of anti-quorum sensing activity in caffeine. Our work will allow caffeine to be explored as anti-infective drugs.
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Affiliation(s)
- Siti Nur Maisarah Norizan
- Division of Genetics and Molecular Biology, Institute of Biological Sciences, Faculty of Science, University of Malaya, Kuala Lumpur 50603, Malaysia.
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Brimacombe CA, Stevens A, Jun D, Mercer R, Lang AS, Beatty JT. Quorum-sensing regulation of a capsular polysaccharide receptor for the Rhodobacter capsulatus gene transfer agent (RcGTA). Mol Microbiol 2013; 87:802-17. [PMID: 23279213 DOI: 10.1111/mmi.12132] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/17/2012] [Indexed: 11/29/2022]
Abstract
The gene transfer agent produced by Rhodobacter capsulatus (RcGTA) resembles a small tailed bacteriophage that packages almost random genomic DNA segments that may be transferred to other R. capsulatus cells. Gene transfer agents are produced by a number of prokaryotes; however, no receptors have been identified. We investigated the RcGTA recipient capability of wild-type R. capsulatus cells at different culture growth phases, and found that the frequency of RcGTA-dependent acquisition of an allele increases as cultures enter the stationary phase. We also found that RcGTA adsorption to cells follows a similar trend. RcGTA recipient capability and adsorption were found to be dependent on the GtaR/I quorum-sensing (QS) system. Production of an extracellular polysaccharide was found to be regulated by GtaR/I QS, as was production of the cell capsule. A number of QS-regulated putative polysaccharide biosynthesis genes were identified, and mutagenesis of two of these genes, rcc01081 and rcc01932, yielded strains that lack a capsule. Furthermore, these mutants were impaired in RcGTA recipient capability and adsorption, as was a non-encapsulated wild-type isolate of R. capsulatus. Overall, our results indicate that capsular polysaccharide is a receptor for the gene transfer agent of R. capsulatus, RcGTA.
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Affiliation(s)
- Cedric A Brimacombe
- Department of Microbiology and Immunology, The University of British Columbia, Vancouver, BC, Canada
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Tanouchi Y, Smith R, You L. Engineering microbial systems to explore ecological and evolutionary dynamics. Curr Opin Biotechnol 2012; 23:791-7. [PMID: 22310174 PMCID: PMC3356794 DOI: 10.1016/j.copbio.2012.01.006] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2011] [Revised: 01/13/2012] [Accepted: 01/14/2012] [Indexed: 01/25/2023]
Abstract
A major goal of biological research is to provide a mechanistic understanding of diverse biological processes. To this end, synthetic biology offers a powerful approach, whereby biological questions can be addressed in a well-defined framework. By constructing simple gene circuits, such studies have generated new insights into the design principles of gene regulatory networks. Recently, this strategy has been applied to analyze ecological and evolutionary questions, where population-level interactions are critical. Here, we highlight recent development of such systems and discuss how they were used to address problems in ecology and evolutionary biology. As illustrated by these examples, synthetic ecosystems provide a unique platform to study ecological and evolutionary phenomena that are challenging to study in their natural contexts.
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Affiliation(s)
- Yu Tanouchi
- Department of Biomedical Engineering, Duke University, Durham, NC, 27708, USA
| | - Robert Smith
- Department of Biomedical Engineering, Duke University, Durham, NC, 27708, USA
| | - Lingchong You
- Department of Biomedical Engineering, Duke University, Durham, NC, 27708, USA
- Institute for Genome Sciences and Policy, Duke University, Durham, NC, 27708, USA
- Center for Systems Biology, Duke University, Durham, NC, 27708, USA
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50
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Cornforth DM, Sumpter DJT, Brown SP, Brännström Å. Synergy and group size in microbial cooperation. Am Nat 2012; 180:296-305. [PMID: 22854073 PMCID: PMC3635123 DOI: 10.1086/667193] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Microbes produce many molecules that are important for their growth and development, and the exploitation of these secretions by nonproducers has recently become an important paradigm in microbial social evolution. Although the production of these public-goods molecules has been studied intensely, little is known of how the benefits accrued and the costs incurred depend on the quantity of public-goods molecules produced. We focus here on the relationship between the shape of the benefit curve and cellular density, using a model assuming three types of benefit functions: diminishing, accelerating, and sigmoidal (accelerating and then diminishing). We classify the latter two as being synergistic and argue that sigmoidal curves are common in microbial systems. Synergistic benefit curves interact with group sizes to give very different expected evolutionary dynamics. In particular, we show that whether and to what extent microbes evolve to produce public goods depends strongly on group size. We show that synergy can create an "evolutionary trap" that can stymie the establishment and maintenance of cooperation. By allowing density-dependent regulation of production (quorum sensing), we show how this trap may be avoided. We discuss the implications of our results on experimental design.
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