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Zhang Z, Pan Y, Hussain W, Chen G, Li E. BBSdb, an open resource for bacterial biofilm-associated proteins. Front Cell Infect Microbiol 2024; 14:1428784. [PMID: 39149420 PMCID: PMC11324577 DOI: 10.3389/fcimb.2024.1428784] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2024] [Accepted: 07/11/2024] [Indexed: 08/17/2024] Open
Abstract
Bacterial biofilms are organized heterogeneous assemblages of microbial cells encased within a self-produced matrix of exopolysaccharides, extracellular DNA and proteins. Over the last decade, more and more biofilm-associated proteins have been discovered and investigated. Furthermore, omics techniques such as transcriptomes, proteomes also play important roles in identifying new biofilm-associated genes or proteins. However, those important data have been uploaded separately to various databases, which creates obstacles for biofilm researchers to have a comprehensive access to these data. In this work, we constructed BBSdb, a state-of-the-art open resource of bacterial biofilm-associated protein. It includes 48 different bacteria species, 105 transcriptome datasets, 21 proteome datasets, 1205 experimental samples, 57,823 differentially expressed genes (DEGs), 13,605 differentially expressed proteins (DEPs), 1,930 'Top 5% differentially expressed genes', 444 'Threshold-based DEGs' and a predictor for prediction of biofilm-associated protein. In addition, 1,781 biofilm-associated proteins, including annotation and sequences, were extracted from 942 articles and public databases via text-mining analysis. We used E. coli as an example to represent how to explore potential biofilm-associated proteins in bacteria. We believe that this study will be of broad interest to researchers in field of bacteria, especially biofilms, which are involved in bacterial growth, pathogenicity, and drug resistance. Availability and implementation: The BBSdb is freely available at http://124.222.145.44/#!/.
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Affiliation(s)
- Zhiyuan Zhang
- State Key Laboratory of Pharmaceutical Biotechnology, Medical School, Nanjing University, Nanjing, Jiangsu, China
- Jiangsu Key Laboratory of Molecular Medicine, Medical School, Nanjing University, Nanjing, Jiangsu, China
- Department of Medical Information Engineering, School of Medical Information, Wannan Medical College, Wuhu, China
| | - Yuanyuan Pan
- Department of Medical Information Engineering, School of Medical Information, Wannan Medical College, Wuhu, China
| | - Wajid Hussain
- Advanced Biomaterials and Tissue Engineering Center, College of Life Sciences and Technology, Huazhong University of Science and Technology, Wuhan, China
| | - Guozhong Chen
- Department of Medical Information Engineering, School of Medical Information, Wannan Medical College, Wuhu, China
| | - Erguang Li
- State Key Laboratory of Pharmaceutical Biotechnology, Medical School, Nanjing University, Nanjing, Jiangsu, China
- Jiangsu Key Laboratory of Molecular Medicine, Medical School, Nanjing University, Nanjing, Jiangsu, China
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2
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Jandl B, Dighe S, Baumgartner M, Makristathis A, Gasche C, Muttenthaler M. Gastrointestinal Biofilms: Endoscopic Detection, Disease Relevance, and Therapeutic Strategies. Gastroenterology 2024:S0016-5085(24)05054-6. [PMID: 38876174 DOI: 10.1053/j.gastro.2024.04.032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Revised: 04/10/2024] [Accepted: 04/15/2024] [Indexed: 06/16/2024]
Abstract
Gastrointestinal biofilms are matrix-enclosed, highly heterogenic and spatially organized polymicrobial communities that can cover large areas in the gastrointestinal tract. Gut microbiota dysbiosis, mucus disruption, and epithelial invasion are associated with pathogenic biofilms that have been linked to gastrointestinal disorders such as irritable bowel syndrome, inflammatory bowel diseases, gastric cancer, and colorectal cancer. Intestinal biofilms are highly prevalent in ulcerative colitis and irritable bowel syndrome patients, and most endoscopists will have observed such biofilms during colonoscopy, maybe without appreciating their biological and clinical importance. Gut biofilms have a protective extracellular matrix that renders them challenging to treat, and effective therapies are yet to be developed. This review covers gastrointestinal biofilm formation, growth, appearance and detection, biofilm architecture and signalling, human host defence mechanisms, disease and clinical relevance of biofilms, therapeutic approaches, and future perspectives. Critical knowledge gaps and open research questions regarding the biofilm's exact pathophysiological relevance and key hurdles in translating therapeutic advances into the clinic are discussed. Taken together, this review summarizes the status quo in gut biofilm research and provides perspectives and guidance for future research and therapeutic strategies.
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Affiliation(s)
- Bernhard Jandl
- Institute of Biological Chemistry, Faculty of Chemistry, University of Vienna, Vienna, Austria; University of Vienna, Vienna Doctoral School in Chemistry, Vienna, Austria; Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia; Division of Gastroenterology and Hepatology, Department of Internal Medicine 3, Medical University of Vienna, Vienna, Austria
| | - Satish Dighe
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia
| | - Maximillian Baumgartner
- Division of Gastroenterology and Hepatology, Department of Internal Medicine 3, Medical University of Vienna, Vienna, Austria; CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Athanasios Makristathis
- Division of Clinical Microbiology, Department of Laboratory Medicine, Medical University of Vienna, Vienna, Austria
| | - Christoph Gasche
- Division of Gastroenterology and Hepatology, Department of Internal Medicine 3, Medical University of Vienna, Vienna, Austria; Loha for Life, Center for Gastroenterology and Iron Deficiency, Vienna, Austria
| | - Markus Muttenthaler
- Institute of Biological Chemistry, Faculty of Chemistry, University of Vienna, Vienna, Austria; Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia.
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3
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Zhang J, Liu Y, Hu J, Leng G, Liu X, Cui Z, Wang W, Ma Y, Sha S. Cellulase Promotes Mycobacterial Biofilm Dispersal in Response to a Decrease in the Bacterial Metabolite Gamma-Aminobutyric Acid. Int J Mol Sci 2024; 25:1051. [PMID: 38256125 PMCID: PMC10816823 DOI: 10.3390/ijms25021051] [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: 12/25/2023] [Revised: 01/08/2024] [Accepted: 01/13/2024] [Indexed: 01/24/2024] Open
Abstract
Biofilm dispersal contributes to bacterial spread and disease transmission. However, its exact mechanism, especially that in the pathogen Mycobacterium tuberculosis, is unclear. In this study, the cellulase activity of the M. tuberculosis Rv0062 protein was characterized, and its effect on mycobacterial biofilm dispersal was analyzed by observation of the structure and components of Rv0062-treated biofilm in vitro. Meanwhile, the metabolite factors that induced cellulase-related biofilm dispersal were also explored with metabolome analysis and further validations. The results showed that Rv0062 protein had a cellulase activity with a similar optimum pH (6.0) and lower optimum temperature (30 °C) compared to the cellulases from other bacteria. It promoted mycobacterial biofilm dispersal by hydrolyzing cellulose, the main component of extracellular polymeric substrates of mycobacterial biofilm. A metabolome analysis revealed that 107 metabolites were significantly altered at different stages of M. smegmatis biofilm development. Among them, a decrease in gamma-aminobutyric acid (GABA) promoted cellulase-related biofilm dispersal, and this effect was realized with the down-regulation of the bacterial signal molecule c-di-GMP. All these findings suggested that cellulase promotes mycobacterial biofilm dispersal and that this process is closely associated with biofilm metabolite alterations.
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Affiliation(s)
- Jiaqi Zhang
- Department of Biochemistry and Molecular Biology, Dalian Medical University, Dalian 116044, China; (J.Z.); (Y.L.); (J.H.); (G.L.); (X.L.); (Z.C.); (W.W.)
| | - Yingying Liu
- Department of Biochemistry and Molecular Biology, Dalian Medical University, Dalian 116044, China; (J.Z.); (Y.L.); (J.H.); (G.L.); (X.L.); (Z.C.); (W.W.)
| | - Junxing Hu
- Department of Biochemistry and Molecular Biology, Dalian Medical University, Dalian 116044, China; (J.Z.); (Y.L.); (J.H.); (G.L.); (X.L.); (Z.C.); (W.W.)
| | - Guangxian Leng
- Department of Biochemistry and Molecular Biology, Dalian Medical University, Dalian 116044, China; (J.Z.); (Y.L.); (J.H.); (G.L.); (X.L.); (Z.C.); (W.W.)
| | - Xining Liu
- Department of Biochemistry and Molecular Biology, Dalian Medical University, Dalian 116044, China; (J.Z.); (Y.L.); (J.H.); (G.L.); (X.L.); (Z.C.); (W.W.)
| | - Zailin Cui
- Department of Biochemistry and Molecular Biology, Dalian Medical University, Dalian 116044, China; (J.Z.); (Y.L.); (J.H.); (G.L.); (X.L.); (Z.C.); (W.W.)
| | - Wenzhen Wang
- Department of Biochemistry and Molecular Biology, Dalian Medical University, Dalian 116044, China; (J.Z.); (Y.L.); (J.H.); (G.L.); (X.L.); (Z.C.); (W.W.)
| | - Yufang Ma
- Department of Biochemistry and Molecular Biology, Dalian Medical University, Dalian 116044, China; (J.Z.); (Y.L.); (J.H.); (G.L.); (X.L.); (Z.C.); (W.W.)
- Department of Microbiology, Dalian Medical University, Dalian 116044, China
| | - Shanshan Sha
- Department of Biochemistry and Molecular Biology, Dalian Medical University, Dalian 116044, China; (J.Z.); (Y.L.); (J.H.); (G.L.); (X.L.); (Z.C.); (W.W.)
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4
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Larabi AB, Masson HLP, Bäumler AJ. Bile acids as modulators of gut microbiota composition and function. Gut Microbes 2023; 15:2172671. [PMID: 36740850 PMCID: PMC9904317 DOI: 10.1080/19490976.2023.2172671] [Citation(s) in RCA: 54] [Impact Index Per Article: 54.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Accepted: 01/16/2023] [Indexed: 02/07/2023] Open
Abstract
Changes in the composition of gut-associated microbial communities are associated with many human illnesses, but the factors driving dysbiosis remain incompletely understood. One factor governing the microbiota composition in the gut is bile. Bile acids shape the microbiota composition through their antimicrobial activity and by activating host signaling pathways that maintain gut homeostasis. Although bile acids are host-derived, their functions are integrally linked to bacterial metabolism, which shapes the composition of the intestinal bile acid pool. Conditions that change the size or composition of the bile acid pool can trigger alterations in the microbiota composition that exacerbate inflammation or favor infection with opportunistic pathogens. Therefore, manipulating the composition or size of the bile acid pool might be a promising strategy to remediate dysbiosis.
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Affiliation(s)
- Anaïs B. Larabi
- Department of Medical Microbiology and Immunology, School of Medicine, University of California at Davis, Davis, CA, USA
| | - Hugo L. P. Masson
- Department of Medical Microbiology and Immunology, School of Medicine, University of California at Davis, Davis, CA, USA
| | - Andreas J. Bäumler
- Department of Medical Microbiology and Immunology, School of Medicine, University of California at Davis, Davis, CA, USA
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5
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Tai JSB, Ferrell MJ, Yan J, Waters CM. New Insights into Vibrio cholerae Biofilms from Molecular Biophysics to Microbial Ecology. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2023; 1404:17-39. [PMID: 36792869 PMCID: PMC10726288 DOI: 10.1007/978-3-031-22997-8_2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
With the discovery that 48% of cholera infections in rural Bangladesh villages could be prevented by simple filtration of unpurified waters and the detection of Vibrio cholerae aggregates in stools from cholera patients it was realized V. cholerae biofilms had a central function in cholera pathogenesis. We are currently in the seventh cholera pandemic, caused by O1 serotypes of the El Tor biotypes strains, which initiated in 1961. It is estimated that V. cholerae annually causes millions of infections and over 100,000 deaths. Given the continued emergence of cholera in areas that lack access to clean water, such as Haiti after the 2010 earthquake or the ongoing Yemen civil war, increasing our understanding of cholera disease remains a worldwide public health priority. The surveillance and treatment of cholera is also affected as the world is impacted by the COVID-19 pandemic, raising significant concerns in Africa. In addition to the importance of biofilm formation in its life cycle, V. cholerae has become a key model system for understanding bacterial signal transduction networks that regulate biofilm formation and discovering fundamental principles about bacterial surface attachment and biofilm maturation. This chapter will highlight recent insights into V. cholerae biofilms including their structure, ecological role in environmental survival and infection, regulatory systems that control them, and biomechanical insights into the nature of V. cholerae biofilms.
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Affiliation(s)
- Jung-Shen B Tai
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, USA
| | - Micah J Ferrell
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI, USA
| | - Jing Yan
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, USA
| | - Christopher M Waters
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI, USA.
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6
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Muhammad AY, Amonov M, Murugaiah C, Baig AA, Yusoff M. Intestinal colonization against Vibrio cholerae: host and microbial resistance mechanisms. AIMS Microbiol 2023; 9:346-374. [PMID: 37091815 PMCID: PMC10113163 DOI: 10.3934/microbiol.2023019] [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: 01/08/2023] [Revised: 03/22/2023] [Accepted: 03/27/2023] [Indexed: 04/25/2023] Open
Abstract
Vibrio cholerae is a non-invasive enteric pathogen known to cause a major public health problem called cholera. The pathogen inhabits the aquatic environment while outside the human host, it is transmitted into the host easily through ingesting contaminated food and water containing the vibrios, thus causing diarrhoea and vomiting. V. cholerae must resist several layers of colonization resistance mechanisms derived from the host or the gut commensals to successfully survive, grow, and colonize the distal intestinal epithelium, thus causing an infection. The colonization resistance mechanisms derived from the host are not specific to V. cholerae but to all invading pathogens. However, some of the gut commensal-derived colonization resistance may be more specific to the pathogen, making it more challenging to overcome. Consequently, the pathogen has evolved well-coordinated mechanisms that sense and utilize the anti-colonization factors to modulate events that promote its survival and colonization in the gut. This review is aimed at discussing how V. cholerae interacts and resists both host- and microbe-specific colonization resistance mechanisms to cause infection.
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Affiliation(s)
| | - Malik Amonov
- Faculty of Medicine, Universiti Sultan Zainal Abidin, Malaysia
- * Correspondence: ; Tel: +60189164478
| | | | - Atif Amin Baig
- University Institute of Public Health, Faculty of Allied Health Sciences, The University of Lahore, Pakistan
| | - Marina Yusoff
- Faculty of Medicine, Universiti Sultan Zainal Abidin, Malaysia
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7
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Pathogens transported by plastic debris: does this vector pose a risk to aquatic organisms? Emerg Top Life Sci 2022; 6:349-358. [PMID: 36205551 DOI: 10.1042/etls20220022] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Revised: 09/14/2022] [Accepted: 09/16/2022] [Indexed: 12/30/2022]
Abstract
Microplastics are small (<5 mm) plastic particles of varying shapes and polymer types that are now widespread global contaminants of marine and freshwater ecosystems. Various estimates suggest that several trillions of microplastic particles are present in our global oceanic system, and that these are readily ingested by a wide range of marine and freshwater species across feeding modes and ecological niches. Here, we present some of the key and pressing issues associated with these globally important contaminants from a microbiological perspective. We discuss the potential mechanisms of pathogen attachment to plastic surfaces. We then describe the ability of pathogens (both human and animal) to form biofilms on microplastics, as well as dispersal of these bacteria, which might lead to their uptake into aquatic species ingesting microplastic particles. Finally, we discuss the role of a changing oceanic system on the potential of microplastic-associated pathogens to cause various disease outcomes using numerous case studies. We set out some key and imperative research questions regarding this globally important issue and present a methodological framework to study how and why plastic-associated pathogens should be addressed.
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8
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Lee HY, Yoon CK, Cho YJ, Lee JW, Lee KA, Lee WJ, Seok YJ. A mannose-sensing AraC-type transcriptional activator regulates cell-cell aggregation of Vibrio cholerae. NPJ Biofilms Microbiomes 2022; 8:65. [PMID: 35987769 PMCID: PMC9392796 DOI: 10.1038/s41522-022-00331-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Accepted: 08/03/2022] [Indexed: 11/18/2022] Open
Abstract
In addition to catalyzing coupled transport and phosphorylation of carbohydrates, the phosphoenolpyruvate:carbohydrate phosphotransferase system (PTS) regulates various physiological processes in most bacteria. Therefore, the transcription of genes encoding the PTS is precisely regulated by transcriptional regulators depending on substrate availability. As the distribution of the mannose-specific PTS (PTSMan) is limited to animal-associated bacteria, it has been suggested to play an important role in host-bacteria interactions. In Vibrio cholerae, mannose is known to inhibit biofilm formation. During host infection, the transcription level of the V. cholerae gene encoding the putative PTSMan (hereafter referred to as manP) significantly increases, and mutations in this gene increase host survival rate. Herein, we show that an AraC-type transcriptional regulator (hereafter referred to as ManR) acts as a transcriptional activator of the mannose operon and is responsible for V. cholerae growth and biofilm inhibition on a mannose or fructose-supplemented medium. ManR activates mannose operon transcription by facilitating RNA polymerase binding to the promoter in response to mannose 6-phosphate and, to a lesser extent, to fructose 1-phosphate. When manP or manR is impaired, the mannose-induced inhibition of biofilm formation was reversed and intestinal colonization was significantly reduced in a Drosophila melanogaster infection model. Our results show that ManR recognizes mannose and fructose in the environment and facilitates V. cholerae survival in the host.
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Affiliation(s)
- Hye-Young Lee
- Department of Biophysics and Chemical Biology, Seoul National University, Seoul, 08826, Republic of Korea
| | - Chang-Kyu Yoon
- School of Biological Sciences and Institute of Microbiology, Seoul National University, Seoul, 08826, Republic of Korea
| | - Yong-Joon Cho
- School of Biological Sciences and Institute of Microbiology, Seoul National University, Seoul, 08826, Republic of Korea
| | - Jin-Woo Lee
- School of Biological Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Kyung-Ah Lee
- School of Biological Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Won-Jae Lee
- School of Biological Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Yeong-Jae Seok
- Department of Biophysics and Chemical Biology, Seoul National University, Seoul, 08826, Republic of Korea.
- School of Biological Sciences and Institute of Microbiology, Seoul National University, Seoul, 08826, Republic of Korea.
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9
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Cho JY, Liu R, Hsiao A. Microbiota-Associated Biofilm Regulation Leads to Vibrio cholerae Resistance Against Intestinal Environmental Stress. Front Cell Infect Microbiol 2022; 12:861677. [PMID: 35573801 PMCID: PMC9095495 DOI: 10.3389/fcimb.2022.861677] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Accepted: 03/25/2022] [Indexed: 11/13/2022] Open
Abstract
The commensal microbes of the gut microbiota make important contributions to host defense against gastrointestinal pathogens, including Vibrio cholerae, the etiologic agent of cholera. As interindividual microbiota variation drives individual differences in infection susceptibility, we examined both host and V. cholerae gene expression during infection of suckling mice transplanted with different model human commensal communities, including an infection-susceptible configuration representing communities damaged by recurrent diarrhea and malnutrition in cholera endemic areas and a representative infection-resistant microbiota characteristic of healthy individuals. In comparison to colonization of animals with resistant microbiota, animals bearing susceptible microbiota challenged with V. cholerae downregulate genes associated with generation of reactive oxygen/nitrogen stress, while V. cholerae in these animals upregulates biofilm-associated genes. We show that V. cholerae in susceptible microbe infection contexts are more resistant to oxidative stress and inhibitory bile metabolites generated by the action of commensal microbes and that both phenotypes are dependent on biofilm-associated genes, including vpsL. We also show that susceptible and infection-resistant microbes drive different bile acid compositions in vivo by the action of bile salt hydrolase enzymes. Taken together, these findings provide a better understanding of how the microbiota uses multiple mechanisms to modulate the infection-associated host environment encountered by V. cholerae, leading to commensal-dependent differences in infection susceptibility.
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Affiliation(s)
- Jennifer Y. Cho
- Department of Microbiology and Plant Pathology, University of California, Riverside, Riverside, CA, United States
- Department of Biochemistry, University of California, Riverside, Riverside, CA, United States
| | - Rui Liu
- Department of Microbiology and Plant Pathology, University of California, Riverside, Riverside, CA, United States
- Graduate Program in Genetics, Genomics, and Bioinformatics, University of California, Riverside, Riverside, CA, United States
| | - Ansel Hsiao
- Department of Microbiology and Plant Pathology, University of California, Riverside, Riverside, CA, United States
- *Correspondence: Ansel Hsiao,
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Yin WL, Xie ZY, Zeng YH, Zhang J, Long H, Ren W, Zhang X, Cai XN, Huang AY. Two (p)ppGpp Synthetase Genes, relA and spoT, Are Involved in Regulating Cell Motility, Exopolysaccharides Production, and Biofilm Formation of Vibrio alginolyticus. Front Microbiol 2022; 13:858559. [PMID: 35422789 PMCID: PMC9002329 DOI: 10.3389/fmicb.2022.858559] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Accepted: 02/28/2022] [Indexed: 12/14/2022] Open
Abstract
The stringent response mediated by the signal molecule (p)ppGpp is involved in response to multiple environmental stresses and control of various physiological processes. Studies have revealed that (p)ppGpp strongly affects the formation and maintenance of several bacterial biofilms. However, the specific regulatory roles of (p)ppGpp in biofilms, especially in the expression of genes related to cell motility and exopolysaccharides (EPSs) production, remain poorly understood. We recently reported two (p)ppGpp synthetase genes relA and spoT from the epizootic pathogen Vibrio alginolyticus. Herein, we found that the (p)ppGpp synthetase genes of V. alginolyticus contributed to biofilm formation at low cell density and biofilm detachment at high cell density, respectively, in polystyrene microtiter plates. Quantitative reverse transcription PCR (qRT-PCR) analysis revealed that the expression levels of both EPSs and motility associated genes were consistent with the development of biofilms. Besides, the (p)ppGpp synthetase gene spoT was found to be closely involved in the regulation of flagellum, smooth/translucent colony morphology and spotty pellicle at the air-liquid interface. Interestingly, pleiotropic phenotypes of ΔrelAΔspoT were similar to that of the rpoN (σ54) deletion mutant. Meanwhile, the absence of (p)ppGpp synthetase genes significantly reduced the expression levels of rpoN at low cell density, suggesting that (p)ppGpp may mediate the formation via positively affecting the alternative sigma factor RpoN. These findings allow us to propose (p)ppGpp as a crucial regulator for biofilm development in V. alginolyticus, in view of the regulatory roles of relA and spoT in cell motility and EPSs production.
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Affiliation(s)
- Wen-Liang Yin
- State Key Laboratory of Marine Resource Utilization in the South China Sea, Hainan University, Haikou, China.,Laboratory of Development and Utilization of Marine Microbial Resource, Hainan University, Haikou, China.,College of Marine Sciences, Hainan University, Haikou, China
| | - Zhen-Yu Xie
- State Key Laboratory of Marine Resource Utilization in the South China Sea, Hainan University, Haikou, China.,Laboratory of Development and Utilization of Marine Microbial Resource, Hainan University, Haikou, China.,College of Marine Sciences, Hainan University, Haikou, China.,Key Laboratory of Tropical Hydrobiology and Biotechnology of Hainan Province, Haikou, China
| | - Yan-Hua Zeng
- State Key Laboratory of Marine Resource Utilization in the South China Sea, Hainan University, Haikou, China.,Laboratory of Development and Utilization of Marine Microbial Resource, Hainan University, Haikou, China
| | - Ju Zhang
- State Key Laboratory of Marine Resource Utilization in the South China Sea, Hainan University, Haikou, China.,Laboratory of Development and Utilization of Marine Microbial Resource, Hainan University, Haikou, China.,College of Marine Sciences, Hainan University, Haikou, China
| | - Hao Long
- State Key Laboratory of Marine Resource Utilization in the South China Sea, Hainan University, Haikou, China.,Laboratory of Development and Utilization of Marine Microbial Resource, Hainan University, Haikou, China
| | - Wei Ren
- State Key Laboratory of Marine Resource Utilization in the South China Sea, Hainan University, Haikou, China.,Laboratory of Development and Utilization of Marine Microbial Resource, Hainan University, Haikou, China.,College of Marine Sciences, Hainan University, Haikou, China.,Key Laboratory of Tropical Hydrobiology and Biotechnology of Hainan Province, Haikou, China
| | - Xiang Zhang
- State Key Laboratory of Marine Resource Utilization in the South China Sea, Hainan University, Haikou, China.,Laboratory of Development and Utilization of Marine Microbial Resource, Hainan University, Haikou, China.,College of Marine Sciences, Hainan University, Haikou, China.,Key Laboratory of Tropical Hydrobiology and Biotechnology of Hainan Province, Haikou, China
| | - Xiao-Ni Cai
- State Key Laboratory of Marine Resource Utilization in the South China Sea, Hainan University, Haikou, China.,Laboratory of Development and Utilization of Marine Microbial Resource, Hainan University, Haikou, China.,College of Marine Sciences, Hainan University, Haikou, China.,Key Laboratory of Tropical Hydrobiology and Biotechnology of Hainan Province, Haikou, China
| | - Ai-You Huang
- State Key Laboratory of Marine Resource Utilization in the South China Sea, Hainan University, Haikou, China.,Laboratory of Development and Utilization of Marine Microbial Resource, Hainan University, Haikou, China.,College of Marine Sciences, Hainan University, Haikou, China.,Key Laboratory of Tropical Hydrobiology and Biotechnology of Hainan Province, Haikou, China
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11
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Bacteroides thetaiotaomicron uses a widespread extracellular DNase to promote bile-dependent biofilm formation. Proc Natl Acad Sci U S A 2022; 119:2111228119. [PMID: 35145026 PMCID: PMC8851478 DOI: 10.1073/pnas.2111228119] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/17/2021] [Indexed: 11/18/2022] Open
Abstract
Biofilms are communities of surface-attached bacteria exhibiting biofilm-specific properties. Although anaerobic biofilms impact health, industry, and environment, they are mostly studied in aerobic bacterial species. Here, we studied biofilm formation in Bacteroides thetaiotaomicron, an anaerobic gut symbiont degrading diet sugars and contributing to gut maturation. Although B. thetaiotaomicron adhesion contributes to intestinal colonization, little is known about the determinants of its biofilm capacities. We identified that bile is a physiologically relevant gut signal inducing biofilm formation in B. thetaiotaomicron and other gut Bacteroidales. Moreover, we showed that, in contrast to the known scaffolding role of extracellular DNA, bile-dependent biofilm requires a DNase degrading matrix DNA, thus revealing a previously unrecognized factor contributing to the adhesion capacity of major gut symbionts. Bacteroides thetaiotaomicron is a gut symbiont that inhabits the mucus layer and adheres to and metabolizes food particles, contributing to gut physiology and maturation. Although adhesion and biofilm formation could be key features for B. thetaiotaomicron stress resistance and gut colonization, little is known about the determinants of B. thetaiotaomicron biofilm formation. We previously showed that the B. thetaiotaomicron reference strain VPI-5482 is a poor in vitro biofilm former. Here, we demonstrated that bile, a gut-relevant environmental cue, triggers the formation of biofilm in many B. thetaiotaomicron isolates and common gut Bacteroidales species. We determined that bile-dependent biofilm formation involves the production of the DNase BT3563 or its homologs, degrading extracellular DNA (eDNA) in several B. thetaiotaomicron strains. Our study therefore shows that, although biofilm matrix eDNA provides a biofilm-promoting scaffold in many studied Firmicutes and Proteobacteria, BT3563-mediated eDNA degradation is required to form B. thetaiotaomicron biofilm in the presence of bile.
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12
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Zareitaher T, Sadat Ahmadi T, Latif Mousavi Gargari S. Immunogenic efficacy of DNA and protein-based vaccine from a chimeric gene consisting OmpW, TcpA and CtxB, ofVibrio cholerae. Immunobiology 2022; 227:152190. [DOI: 10.1016/j.imbio.2022.152190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 01/30/2022] [Accepted: 02/12/2022] [Indexed: 11/16/2022]
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13
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Wang G, Mohanty B, Williams ML, Doak BC, Dhouib R, Totsika M, McMahon R, Sharma G, Zheng D, Bentley MR, Chin YKY, Horne J, Chalmers DK, Heras B, Scanlon MJ. Selective binding of small molecules to Vibrio cholerae DsbA offers a starting point for the design of novel antibacterials. ChemMedChem 2022; 17:e202100673. [PMID: 34978144 PMCID: PMC9305425 DOI: 10.1002/cmdc.202100673] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 12/23/2021] [Indexed: 11/25/2022]
Abstract
DsbA enzymes catalyze oxidative folding of proteins that are secreted into the periplasm of Gram‐negative bacteria, and they are indispensable for the virulence of human pathogens such as Vibrio cholerae and Escherichia coli. Therefore, targeting DsbA represents an attractive approach to control bacterial virulence. X‐ray crystal structures reveal that DsbA enzymes share a similar fold, however, the hydrophobic groove adjacent to the active site, which is implicated in substrate binding, is shorter and flatter in the structure of V. cholerae DsbA (VcDsbA) compared to E. coli DsbA (EcDsbA). The flat and largely featureless nature of this hydrophobic groove is challenging for the development of small molecule inhibitors. Using fragment‐based screening approaches, we have identified a novel small molecule, based on the benzimidazole scaffold, that binds to the hydrophobic groove of oxidized VcDsbA with a KD of 446±10 μM. The same benzimidazole compound has ∼8‐fold selectivity for VcDsbA over EcDsbA and binds to oxidized EcDsbA, with KD>3.5 mM. We generated a model of the benzimidazole complex with VcDsbA using NMR data but were unable to determine the structure of the benzimidazole bound EcDsbA using either NMR or X‐ray crystallography. Therefore, a structural basis for the observed selectivity is unclear. To better understand ligand binding to these two enzymes we crystallized each of them in complex with a known ligand, the bile salt sodium taurocholate. The crystal structures show that taurocholate adopts different binding poses in complex with VcDsbA and EcDsbA, and reveal the protein‐ligand interactions that stabilize the different modes of binding. This work highlights the capacity of fragment‐based drug discovery to identify inhibitors of challenging protein targets. In addition, it provides a starting point for development of more potent and specific VcDsbA inhibitors that act through a novel anti‐virulence mechanism.
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Affiliation(s)
- Geqing Wang
- La Trobe University - Bundoora Campus: La Trobe University, Department of Biochemistry and Genetics, AUSTRALIA
| | | | - Martin L Williams
- Monash Institute of Pharmaceutical Sciences, Medicinal Chemistry, AUSTRALIA
| | - Bradley C Doak
- Monash Institute of Pharmaceutical Sciences, Medicinal Chemistry, AUSTRALIA
| | - Rabeb Dhouib
- Queensland University of Technology, School of Biomedical Sciences, AUSTRALIA
| | - Makrina Totsika
- Queensland University of Technology, School of Biomedical Sciences, AUSTRALIA
| | - Roisin McMahon
- Griffith University, Griffith Institute for Drug Discovery, AUSTRALIA
| | - Gaurav Sharma
- Monash Institute of Pharmaceutical Sciences, Medicinal Chemistry, AUSTRALIA
| | - Dan Zheng
- Monash Institute of Pharmaceutical Sciences, Medicinal Chemistry, AUSTRALIA
| | - Matthew R Bentley
- Monash Institute of Pharmaceutical Sciences, Medicinal Chemistry, AUSTRALIA
| | - Yanni Ka-Yan Chin
- The University of Queensland, Cantre for Advanced Imaging, AUSTRALIA
| | - James Horne
- University of Tasmania, Central Science Laboratory, AUSTRALIA
| | - David K Chalmers
- Monash Institute of Pharmaceutical Sciences, Medicinal Chemistry, AUSTRALIA
| | - Begoña Heras
- La Trobe University, Department of Biochemistry and Genetics, AUSTRALIA
| | - Martin Joseph Scanlon
- Monash Institute of Pharmaceutical Sciences Monash University Parkville Campus, Medicinal Chemistry, 381 Royal Parade, Monash University, 3052, Parkville, AUSTRALIA
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14
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Béchon N, Ghigo JM. Gut biofilms: Bacteroides as model symbionts to study biofilm formation by intestinal anaerobes. FEMS Microbiol Rev 2021; 46:6440158. [PMID: 34849798 DOI: 10.1093/femsre/fuab054] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Accepted: 11/09/2021] [Indexed: 02/06/2023] Open
Abstract
Bacterial biofilms are communities of adhering bacteria that express distinct properties compared to their free-living counterparts, including increased antibiotic tolerance and original metabolic capabilities. Despite the potential impact of the biofilm lifestyle on the stability and function of the dense community of micro-organisms constituting the mammalian gut microbiota, the overwhelming majority of studies performed on biofilm formation by gut bacteria focused either on minor and often aerobic members of the community or on pathogenic bacteria. In this review, we discuss the reported evidence for biofilm-like structures formed by gut bacteria, the importance of considering the anaerobic nature of gut biofilms and we present the most recent advances on biofilm formation by Bacteroides, one of the most abundant genera of the human gut microbiota. Bacteroides species can be found attached to food particles and colonizing the mucus layer and we propose that Bacteroides symbionts are relevant models to probe the physiology of gut microbiota biofilms.
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Affiliation(s)
- Nathalie Béchon
- Institut Pasteur, Université de Paris, UMR CNRS2001, Genetics of Biofilms Laboratory 75015 Paris, France
| | - Jean-Marc Ghigo
- Institut Pasteur, Université de Paris, UMR CNRS2001, Genetics of Biofilms Laboratory 75015 Paris, France
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15
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Kumar R, Tung TC, Ng TH, Chang CC, Chen YL, Chen YM, Lin SS, Wang HC. Metabolic Alterations in Shrimp Stomach During Acute Hepatopancreatic Necrosis Disease and Effects of Taurocholate on Vibrio parahaemolyticus. Front Microbiol 2021; 12:631468. [PMID: 33959104 PMCID: PMC8093816 DOI: 10.3389/fmicb.2021.631468] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Accepted: 03/10/2021] [Indexed: 12/27/2022] Open
Abstract
Acute hepatopancreatic necrosis disease (AHPND), a recently emerged bacterial shrimp disease, has increased shrimp mortality and caused huge economic losses in many Asian countries. However, molecular factors underlying pathogenesis of this disease remain largely unknown. Our objective was to characterize metabolic alterations in shrimp stomach during AHPND and determine effects of taurocholate on AHPND-causing Vibrio parahaemolyticus. Based on metabolomics, pathways for lipid metabolism and for primary bile acid (BA) synthesis were majorly affected following AHPND infection. Bile acid metabolites, namely taurocholate, were downregulated in the metabolomics database. This prompted us to study effects of taurocholate on biofilm formation, PirAB vp toxin release and biofilm detachment capabilities in AHPND-causing V. parahaemolyticus. Treatment of this bacterium with high concentration of taurocholate, a primary bile acid, induced biofilm formation, PirAB vp toxin release and facilitated the dispersion of bacterial cells. Taken together, our findings suggest that AHPND infection can affect the lipid metabolites in shrimp stomach, and further suggest that the primary bile acid taurocholate is important for the virulence of AHPND-causing V. parahaemolyticus.
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Affiliation(s)
- Ramya Kumar
- Department of Biotechnology and Bioindustry Sciences, National Cheng Kung University, Tainan, Taiwan.,International Center for Scientific Development of Shrimp Aquaculture, National Cheng Kung University, Tainan, Taiwan
| | - Teng-Chun Tung
- Department of Biotechnology and Bioindustry Sciences, National Cheng Kung University, Tainan, Taiwan
| | - Tze Hann Ng
- International Center for Scientific Development of Shrimp Aquaculture, National Cheng Kung University, Tainan, Taiwan.,Institute for Evolution and Biodiversity, University of Münster, Münster, Germany
| | - Che-Chih Chang
- Department of Biotechnology and Bioindustry Sciences, National Cheng Kung University, Tainan, Taiwan
| | - Yi-Lun Chen
- Department of Biotechnology and Bioindustry Sciences, National Cheng Kung University, Tainan, Taiwan
| | - Yi-Min Chen
- Department of Biotechnology and Bioindustry Sciences, National Cheng Kung University, Tainan, Taiwan.,International Center for Scientific Development of Shrimp Aquaculture, National Cheng Kung University, Tainan, Taiwan
| | - Shih-Shun Lin
- Institute of Biotechnology, National Taiwan University, Taipei, Taiwan
| | - Han-Ching Wang
- Department of Biotechnology and Bioindustry Sciences, National Cheng Kung University, Tainan, Taiwan.,International Center for Scientific Development of Shrimp Aquaculture, National Cheng Kung University, Tainan, Taiwan
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16
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Cho JY, Liu R, Macbeth JC, Hsiao A. The Interface of Vibrio cholerae and the Gut Microbiome. Gut Microbes 2021; 13:1937015. [PMID: 34180341 PMCID: PMC8244777 DOI: 10.1080/19490976.2021.1937015] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Revised: 05/18/2021] [Accepted: 05/24/2021] [Indexed: 02/04/2023] Open
Abstract
The bacterium Vibrio cholerae is the etiologic agent of the severe human diarrheal disease cholera. The gut microbiome, or the native community of microorganisms found in the human gastrointestinal tract, is increasingly being recognized as a factor in driving susceptibility to infection, in vivo fitness, and host interactions of this pathogen. Here, we review a subset of the emerging studies in how gut microbiome structure and microbial function are able to drive V. cholerae virulence gene regulation, metabolism, and modulate host immune responses to cholera infection and vaccination. Improved mechanistic understanding of commensal-pathogen interactions offers new perspectives in the design of prophylactic and therapeutic approaches for cholera control.
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Affiliation(s)
- Jennifer Y. Cho
- Department of Microbiology and Plant Pathology, University of California, Riverside, CA, USA
- Department of Biochemistry, University of California, Riverside, California, USA
| | - Rui Liu
- Department of Microbiology and Plant Pathology, University of California, Riverside, CA, USA
- Graduate Program in Genetics, Genomics, and Bioinformatics, University of California, Riverside, California, USA
| | - John C. Macbeth
- Department of Microbiology and Plant Pathology, University of California, Riverside, CA, USA
- Division of Biomedical Sciences, School of Medicine, University of California, Riverside, California, USA
| | - Ansel Hsiao
- Department of Microbiology and Plant Pathology, University of California, Riverside, CA, USA
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17
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Bridges AA, Fei C, Bassler BL. Identification of signaling pathways, matrix-digestion enzymes, and motility components controlling Vibrio cholerae biofilm dispersal. Proc Natl Acad Sci U S A 2020; 117:32639-32647. [PMID: 33288715 PMCID: PMC7768729 DOI: 10.1073/pnas.2021166117] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Bacteria alternate between being free-swimming and existing as members of sessile multicellular communities called biofilms. The biofilm lifecycle occurs in three stages: cell attachment, biofilm maturation, and biofilm dispersal. Vibrio cholerae biofilms are hyperinfectious, and biofilm formation and dispersal are considered central to disease transmission. While biofilm formation is well studied, almost nothing is known about biofilm dispersal. Here, we conducted an imaging screen for V. cholerae mutants that fail to disperse, revealing three classes of dispersal components: signal transduction proteins, matrix-degradation enzymes, and motility factors. Signaling proteins dominated the screen and among them, we focused on an uncharacterized two-component sensory system that we term DbfS/DbfR for dispersal of biofilm sensor/regulator. Phospho-DbfR represses biofilm dispersal. DbfS dephosphorylates and thereby inactivates DbfR, which permits dispersal. Matrix degradation requires two enzymes: LapG, which cleaves adhesins, and RbmB, which digests matrix polysaccharides. Reorientation in swimming direction, mediated by CheY3, is necessary for cells to escape from the porous biofilm matrix. We suggest that these components act sequentially: signaling launches dispersal by terminating matrix production and triggering matrix digestion, and subsequent cell motility permits escape from biofilms. This study lays the groundwork for interventions aimed at modulating V. cholerae biofilm dispersal to ameliorate disease.
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Affiliation(s)
- Andrew A Bridges
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544
- HHMI, Chevy Chase, MD 20815
| | - Chenyi Fei
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544
| | - Bonnie L Bassler
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544;
- HHMI, Chevy Chase, MD 20815
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18
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Hsiao A, Zhu J. Pathogenicity and virulence regulation of Vibrio cholerae at the interface of host-gut microbiome interactions. Virulence 2020; 11:1582-1599. [PMID: 33172314 PMCID: PMC7671094 DOI: 10.1080/21505594.2020.1845039] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 10/27/2020] [Accepted: 10/28/2020] [Indexed: 12/12/2022] Open
Abstract
The Gram-negative bacterium Vibrio cholerae is responsible for the severe diarrheal pandemic disease cholera, representing a major global public health concern. This pathogen transitions from aquatic reservoirs into epidemics in human populations, and has evolved numerous mechanisms to sense this transition in order to appropriately regulate its gene expression for infection. At the intersection of pathogen and host in the gastrointestinal tract lies the community of native gut microbes, the gut microbiome. It is increasingly clear that the diversity of species and biochemical activities within the gut microbiome represents a driver of infection outcome, through their ability to manipulate the signals used by V. cholerae to regulate virulence and fitness in vivo. A better mechanistic understanding of how commensal microbial action interacts with V. cholerae pathogenesis may lead to novel prophylactic and therapeutic interventions for cholera. Here, we review a subset of this burgeoning field of research.
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Affiliation(s)
- Ansel Hsiao
- Department of Microbiology & Plant Pathology, University of California Riverside, Riverside, CA, USA
| | - Jun Zhu
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
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19
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Taheri F, Nazarian S, Ahmadi TS, Gargari SLM. Protective effects of egg yolk immunoglobulins (IgYs) developed against recombinant immunogens CtxB, OmpW and TcpA on infant mice infected with Vibrio cholerae. Int Immunopharmacol 2020; 89:107054. [DOI: 10.1016/j.intimp.2020.107054] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2020] [Revised: 09/25/2020] [Accepted: 09/25/2020] [Indexed: 12/11/2022]
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20
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Qin Z, Yang X, Chen G, Park C, Liu Z. Crosstalks Between Gut Microbiota and Vibrio Cholerae. Front Cell Infect Microbiol 2020; 10:582554. [PMID: 33194819 PMCID: PMC7644805 DOI: 10.3389/fcimb.2020.582554] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2020] [Accepted: 09/17/2020] [Indexed: 12/11/2022] Open
Abstract
Vibrio cholerae, the causative agent of cholera, could proliferate in aquatic environment and infect humans through contaminated food and water. Enormous microorganisms residing in human gastrointestinal tract establish a special microecological system, which immediately responds to the invasion of V. cholerae, through “colonization resistance” mechanisms, such as antimicrobial peptide production, nutrients competition, and intestinal barrier maintenances. Meanwhile, V. cholerae could quickly sense those signals and modulate the expression of relevant genes to circumvent those stresses during infection, leading to successful colonization on the surface of small intestinal epithelial cells. In this review, we summarized the crosstalks profiles between gut microbiota and V. cholerae in the terms of Type VI Secretion System (T6SS), Quorum Sensing (QS), Reactive Oxygen Species (ROS)/pH stress, and Bioactive metabolites. These mechanisms can also be applied to molecular bacterial pathogenesis of other pathogens in host.
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Affiliation(s)
- Zixin Qin
- Department of Biotechnology, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, China
| | - Xiaoman Yang
- Department of Biotechnology, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, China
| | - Guozhong Chen
- Department of Biotechnology, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, China
| | - Chaiwoo Park
- Department of Biotechnology, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, China
| | - Zhi Liu
- Department of Biotechnology, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, China
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21
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Biswas S, Chouhan OP, Bandekar D. Diguanylate Cyclases in Vibrio cholerae: Essential Regulators of Lifestyle Switching. Front Cell Infect Microbiol 2020; 10:582947. [PMID: 33194821 PMCID: PMC7642852 DOI: 10.3389/fcimb.2020.582947] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Accepted: 09/14/2020] [Indexed: 01/04/2023] Open
Abstract
Biofilm formation in Vibrio cholerae empowers the bacteria to lead a dual lifestyle and enhances its infectivity. While the formation and dispersal of the biofilm involves multiple components—both proteinaceous and non-proteinaceous, the key to the regulatory control lies with the ubiquitous secondary signaling molecule, cyclic-di-GMP (c-di-GMP). A number of different cellular components may interact with c-di-GMP, but the onus of synthesis of this molecule lies with a class of enzymes known as diguanylate cyclases (DGCs). DGC activity is generally associated with proteins possessing a GGDEF domain, ubiquitously present across all bacterial systems. V. cholerae is also endowed with multiple DGCs and information about some of them have been pouring in over the past decade. This review summarizes the DGCs confirmed till date in V. cholerae, and emphasizes the importance of DGCs and their product, c-di-GMP in the virulence and lifecycle of the bacteria.
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Affiliation(s)
- Sumit Biswas
- ViStA Lab, Department of Biological Sciences, Birla Institute of Technology and Sciences (BITS), Pilani-KK Birla Goa Campus, Goa, India
| | - Om Prakash Chouhan
- ViStA Lab, Department of Biological Sciences, Birla Institute of Technology and Sciences (BITS), Pilani-KK Birla Goa Campus, Goa, India
| | - Divya Bandekar
- ViStA Lab, Department of Biological Sciences, Birla Institute of Technology and Sciences (BITS), Pilani-KK Birla Goa Campus, Goa, India
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22
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Condren AR, Kahl LJ, Boelter G, Kritikos G, Banzhaf M, Dietrich LEP, Sanchez LM. Biofilm Inhibitor Taurolithocholic Acid Alters Colony Morphology, Specialized Metabolism, and Virulence of Pseudomonas aeruginosa. ACS Infect Dis 2020; 6:603-612. [PMID: 31851822 DOI: 10.1021/acsinfecdis.9b00424] [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] [Indexed: 02/08/2023]
Abstract
Biofilm inhibition by exogenous molecules has been an attractive strategy for the development of novel therapeutics. We investigated the biofilm inhibitor taurolithocholic acid (TLCA) and its effects on the specialized metabolism, virulence, and biofilm formation of the clinically relevant bacterium Pseudomonas aeruginosa strain PA14. Our study shows that TLCA alters the specialized metabolism, thereby affecting P. aeruginosa colony biofilm physiology. We observed an upregulation of metabolites correlated to virulence such as the siderophore pyochelin. A wax moth virulence assay confirmed that treatment with TLCA increases the virulence of P. aeruginosa. On the basis of our results, we believe that future endeavors to identify biofilm inhibitors must consider how a putative lead alters the specialized metabolism of a bacterial community to prevent pathogens from entering a highly virulent state.
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Affiliation(s)
- Alanna R. Condren
- Department of Pharmaceutical Sciences, University of Illinois at Chicago, 833 South Wood Street, Chicago, Illinois 60612, United States
| | - Lisa Juliane Kahl
- Department of Biological Sciences, Columbia University, 617 Fairchild Center, New York, New York 10027, United States
| | - Gabriela Boelter
- Institute of Microbiology & Infection and School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, U.K
| | - George Kritikos
- Institute of Microbiology & Infection and School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, U.K
| | - Manuel Banzhaf
- Institute of Microbiology & Infection and School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, U.K
| | - Lars E. P. Dietrich
- Department of Biological Sciences, Columbia University, 617 Fairchild Center, New York, New York 10027, United States
| | - Laura M. Sanchez
- Department of Pharmaceutical Sciences, University of Illinois at Chicago, 833 South Wood Street, Chicago, Illinois 60612, United States
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23
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Xi D, Yang S, Liu Q, Li Y, Li Y, Yan J, Wang X, Ning K, Cao B. The response regulator ArcA enhances biofilm formation in the vpsT manner under the anaerobic condition in Vibrio cholerae. Microb Pathog 2020; 144:104197. [PMID: 32283260 DOI: 10.1016/j.micpath.2020.104197] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 04/04/2020] [Accepted: 04/06/2020] [Indexed: 12/27/2022]
Abstract
Vibrio cholerae, the agent of severe diarrheal disease cholera, is known to form biofilm to persist in the environmental and the host,s intestines. The bacteria execute a complex regulatory pathway producing virulence factors that allow colonization and cause disease in response to environmental signals in the intestine, including low oxygen-limited condition. VpsR and VpsT are primary regulators of the biofilm formation-regulatory network. In this study, we determined that anaerobic induction enhanced biofilm formation via the two component system, ArcB/A, which functions as a positive regulator of toxT expression. The biofilm formation has reduced approximately 2.4-fold in the ΔarcA mutant compared to the wild type in anaerobic condition. Chip-qPCR and EMSA assays confirmed that ArcA can bind directly to the vpsT promoter and then activates the expression of biofilm formation related genes, vpsA-K and vpsL-Q. Meanwhile, the ΔarcA mutant decreased the ability of colonization in intestine with CI (competition index) of 0.27 compared to wild type strain. These results suggest that ArcA links the expression of virulence and biofilm synthesis genes during anaerobic condition, and contributes to understand the complex relationship between biofilm formation and the intestinal signals during infection.
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Affiliation(s)
- Daoyi Xi
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, 300457, China; Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Nankai University, Tianjin, 300457, China; Tianjin Key Laboratory of Microbial Functional Genomics, TEDA College, Nankai University, Tianjin, 300457, China
| | - Shuang Yang
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, 300457, China; Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Nankai University, Tianjin, 300457, China; Tianjin Key Laboratory of Microbial Functional Genomics, TEDA College, Nankai University, Tianjin, 300457, China
| | - Qian Liu
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, 300457, China; Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Nankai University, Tianjin, 300457, China; Tianjin Key Laboratory of Microbial Functional Genomics, TEDA College, Nankai University, Tianjin, 300457, China
| | - Yujia Li
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, 300457, China; Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Nankai University, Tianjin, 300457, China; Tianjin Key Laboratory of Microbial Functional Genomics, TEDA College, Nankai University, Tianjin, 300457, China
| | - Yuehua Li
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, 300457, China; Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Nankai University, Tianjin, 300457, China; Tianjin Key Laboratory of Microbial Functional Genomics, TEDA College, Nankai University, Tianjin, 300457, China
| | - Junxiang Yan
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, 300457, China; Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Nankai University, Tianjin, 300457, China; Tianjin Key Laboratory of Microbial Functional Genomics, TEDA College, Nankai University, Tianjin, 300457, China
| | - Xiaochen Wang
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, 300457, China; Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Nankai University, Tianjin, 300457, China; Tianjin Key Laboratory of Microbial Functional Genomics, TEDA College, Nankai University, Tianjin, 300457, China
| | - Kexin Ning
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, 300457, China; Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Nankai University, Tianjin, 300457, China; Tianjin Key Laboratory of Microbial Functional Genomics, TEDA College, Nankai University, Tianjin, 300457, China
| | - Boyang Cao
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, 300457, China; Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Nankai University, Tianjin, 300457, China; Tianjin Key Laboratory of Microbial Functional Genomics, TEDA College, Nankai University, Tianjin, 300457, China.
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24
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The quorum sensing transcription factor AphA directly regulates natural competence in Vibrio cholerae. PLoS Genet 2019; 15:e1008362. [PMID: 31658256 PMCID: PMC6855506 DOI: 10.1371/journal.pgen.1008362] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Revised: 11/14/2019] [Accepted: 10/16/2019] [Indexed: 01/30/2023] Open
Abstract
Many bacteria use population density to control gene expression via quorum sensing. In Vibrio cholerae, quorum sensing coordinates virulence, biofilm formation, and DNA uptake by natural competence. The transcription factors AphA and HapR, expressed at low and high cell density respectively, play a key role. In particular, AphA triggers the entire virulence cascade upon host colonisation. In this work we have mapped genome-wide DNA binding by AphA. We show that AphA is versatile, exhibiting distinct modes of DNA binding and promoter regulation. Unexpectedly, whilst HapR is known to induce natural competence, we demonstrate that AphA also intervenes. Most notably, AphA is a direct repressor of tfoX, the master activator of competence. Hence, production of AphA markedly suppressed DNA uptake; an effect largely circumvented by ectopic expression of tfoX. Our observations suggest dual regulation of competence. At low cell density AphA is a master repressor whilst HapR activates the process at high cell density. Thus, we provide deep mechanistic insight into the role of AphA and highlight how V. cholerae utilises this regulator for diverse purposes. Cholera remains a devastating diarrhoeal disease responsible for millions of cases, thousands of deaths, and a $3 billion financial burden every year. Although notorious for causing human disease, the microorganism responsible for cholera is predominantly a resident of aquatic environments. Here, the organism survives in densely packed communities on the surfaces of crustaceans. Remarkably, in this situation, the microbe can feast on neighbouring cells and acquire their DNA. This provides a useful food source and an opportunity to obtain new genetic information. In this paper, we have investigated how acquisition of DNA from the local environment is regulated. We show that a “switch” within the microbial cell, known to activate disease processes in the human host, also controls DNA uptake. Our results explain why DNA scavenging only occurs in suitable environments and illustrates how interactions between common regulatory switches affords precise control of microbial behaviours.
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Guilhen C, Miquel S, Charbonnel N, Joseph L, Carrier G, Forestier C, Balestrino D. Colonization and immune modulation properties of Klebsiella pneumoniae biofilm-dispersed cells. NPJ Biofilms Microbiomes 2019; 5:25. [PMID: 31583108 PMCID: PMC6760147 DOI: 10.1038/s41522-019-0098-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Accepted: 08/12/2019] [Indexed: 02/07/2023] Open
Abstract
Biofilm-dispersal is a key determinant for further dissemination of biofilm-embedded bacteria. Recent evidence indicates that biofilm-dispersed bacteria have transcriptional features different from those of both biofilm and planktonic bacteria. In this study, the in vitro and in vivo phenotypic properties of Klebsiella pneumoniae cells spontaneously dispersed from biofilm were compared with those of planktonic and sessile cells. Biofilm-dispersed cells, whose growth rate was the same as that of exponential planktonic bacteria but significantly higher than those of sessile and stationary planktonic forms, colonized both abiotic and biotic surfaces more efficiently than their planktonic counterparts regardless of their initial adhesion capabilities. Microscopy studies suggested that dispersed bacteria initiate formation of microcolonies more rapidly than planktonic bacteria. In addition, dispersed cells have both a higher engulfment rate and better survival/multiplication inside macrophages than planktonic cells and sessile cells. In an in vivo murine pneumonia model, the bacterial load in mice lungs infected with biofilm-dispersed bacteria was similar at 6, 24 and 48 h after infection to that of mice lungs infected with planktonic or sessile bacteria. However, biofilm-dispersed and sessile bacteria trend to elicit innate immune response in lungs to a lesser extent than planktonic bacteria. Collectively, the findings from this study suggest that the greater ability of K. pneumoniae biofilm-dispersed cells to efficiently achieve surface colonization and to subvert the host immune response confers them substantial advantages in the first steps of the infection process over planktonic bacteria.
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Affiliation(s)
- Cyril Guilhen
- 1Université Clermont Auvergne, CNRS 6023, LMGE, Clermont-Ferrand, France.,3Present Address: Université de Genève, Centre Médical Universitaire, Département de Physiologie Cellulaire et Métabolisme, Genève, Suisse
| | - Sylvie Miquel
- 1Université Clermont Auvergne, CNRS 6023, LMGE, Clermont-Ferrand, France
| | - Nicolas Charbonnel
- 1Université Clermont Auvergne, CNRS 6023, LMGE, Clermont-Ferrand, France
| | - Laura Joseph
- 1Université Clermont Auvergne, CNRS 6023, LMGE, Clermont-Ferrand, France
| | - Guillaume Carrier
- 2Université Clermont Auvergne, Inserm U1071, USC-INRA 2018, M2iSH, CRNH Auvergne, Clermont-Ferrand, France.,4Present Address: Department of Surgical Oncology, Institut du Cancer de Montpellier, Montpellier, France
| | | | - Damien Balestrino
- 1Université Clermont Auvergne, CNRS 6023, LMGE, Clermont-Ferrand, France
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Peterson KM, Gellings PS. Multiple intraintestinal signals coordinate the regulation of Vibrio cholerae virulence determinants. Pathog Dis 2018; 76:4791527. [PMID: 29315383 DOI: 10.1093/femspd/ftx126] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Accepted: 12/27/2017] [Indexed: 12/17/2022] Open
Abstract
Vibrio cholerae is a Gram-negative motile bacterium capable of causing fatal pandemic disease in humans via oral ingestion of contaminated water or food. Within the human intestine, the motile vibrios must evade the innate host defense mechanisms, penetrate the mucus layer covering the small intestine, adhere to and multiply on the surface of the microvilli and cause disease via the action of cholera toxin. The explosive diarrhea associated with V. cholerae intestinal colonization leads to dissemination of the vibrios back into the environment to complete this phase of the life cycle. The host phase of the vibrio life cycle is made possible via the concerted action of a signaling cascade that controls the synthesis of V. cholerae colonization determinants. These virulence proteins are coordinately synthesized in response to specific host signals that are still largely undefined. A more complete understanding of the molecular events involved in the V. cholerae recognition of intraintestinal signals and the subsequent transcriptional response will provide important information regarding how pathogenic bacteria establish infection and provide novel methods for treating and/or preventing bacterial infections such as Asiatic cholera. This review will summarize what is currently known in regard to host intraintestinal signals that inform the complex ToxR regulatory cascade in order to coordinate in a spatial and temporal fashion virulence protein synthesis within the human small intestine.
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Affiliation(s)
- Kenneth M Peterson
- Department of Microbiology and Immunology, Louisiana State University Health Science Center, Shreveport, LA 71130, USA
| | - Patrick S Gellings
- Department of Microbiology and Immunology, Louisiana State University Health Science Center, Shreveport, LA 71130, USA
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Mechanisms of Bacterial Tolerance and Persistence in the Gastrointestinal and Respiratory Environments. Clin Microbiol Rev 2018; 31:31/4/e00023-18. [PMID: 30068737 DOI: 10.1128/cmr.00023-18] [Citation(s) in RCA: 103] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Pathogens that infect the gastrointestinal and respiratory tracts are subjected to intense pressure due to the environmental conditions of the surroundings. This pressure has led to the development of mechanisms of bacterial tolerance or persistence which enable microorganisms to survive in these locations. In this review, we analyze the general stress response (RpoS mediated), reactive oxygen species (ROS) tolerance, energy metabolism, drug efflux pumps, SOS response, quorum sensing (QS) bacterial communication, (p)ppGpp signaling, and toxin-antitoxin (TA) systems of pathogens, such as Escherichia coli, Salmonella spp., Vibrio spp., Helicobacter spp., Campylobacter jejuni, Enterococcus spp., Shigella spp., Yersinia spp., and Clostridium difficile, all of which inhabit the gastrointestinal tract. The following respiratory tract pathogens are also considered: Staphylococcus aureus, Pseudomonas aeruginosa, Acinetobacter baumannii, Burkholderia cenocepacia, and Mycobacterium tuberculosis Knowledge of the molecular mechanisms regulating the bacterial tolerance and persistence phenotypes is essential in the fight against multiresistant pathogens, as it will enable the identification of new targets for developing innovative anti-infective treatments.
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28
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Enright EF, Griffin BT, Gahan CG, Joyce SA. Microbiome-mediated bile acid modification: Role in intestinal drug absorption and metabolism. Pharmacol Res 2018; 133:170-186. [DOI: 10.1016/j.phrs.2018.04.009] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Revised: 04/07/2018] [Accepted: 04/12/2018] [Indexed: 01/03/2023]
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Baranova DE, Levinson KJ, Mantis NJ. Vibrio cholerae O1 secretes an extracellular matrix in response to antibody-mediated agglutination. PLoS One 2018; 13:e0190026. [PMID: 29293563 PMCID: PMC5749738 DOI: 10.1371/journal.pone.0190026] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Accepted: 12/06/2017] [Indexed: 11/29/2022] Open
Abstract
Vibrio cholerae O1 is one of two serogroups responsible for epidemic cholera, a severe watery diarrhea that occurs after the bacterium colonizes the human small intestine and secretes a potent ADP-ribosylating toxin. Immunity to cholera is associated with intestinal anti-lipopolysaccharide (LPS) antibodies, which are known to inhibit V. cholerae motility and promote bacterial cell-cell crosslinking and aggregation. Here we report that V. cholerae O1 classical and El Tor biotypes produce an extracellular matrix (ECM) when forcibly immobilized and agglutinated by ZAC-3 IgG, an intestinally-derived monoclonal antibody (MAb) against the core/lipid A region of LPS. ECM secretion, as demonstrated by crystal violet staining and scanning electron microscopy, occurred within 30 minutes of antibody exposure and peaked by 3 hours. Non-motile mutants of V. cholerae did not secrete ECM following ZAC-3 IgG exposure, even though they were susceptible to agglutination. The ECM was enriched in O-specific polysaccharide (OSP) but not Vibrio polysaccharide (VPS). Finally, we demonstrate that ECM production by V. cholerae in response to ZAC-3 IgG was associated with bacterial resistant to a secondary complement-mediated attack. In summary, we propose that V. cholerae O1, upon encountering anti-LPS antibodies in the intestinal lumen, secretes an ECM (or O-antigen capsule) possibly as a strategy to shield itself from additional host immune factors and to exit an otherwise inhospitable host environment.
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Affiliation(s)
- Danielle E. Baranova
- Department of Biomedical Sciences, University at Albany, Albany, NY, United States of America
- Division of Infectious Diseases, Wadsworth Center, New York State Department of Health, Albany, NY, United States of America
| | - Kara J. Levinson
- Department of Biomedical Sciences, University at Albany, Albany, NY, United States of America
- Division of Infectious Diseases, Wadsworth Center, New York State Department of Health, Albany, NY, United States of America
| | - Nicholas J. Mantis
- Department of Biomedical Sciences, University at Albany, Albany, NY, United States of America
- Division of Infectious Diseases, Wadsworth Center, New York State Department of Health, Albany, NY, United States of America
- * E-mail:
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30
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Singh PK, Bartalomej S, Hartmann R, Jeckel H, Vidakovic L, Nadell CD, Drescher K. Vibrio cholerae Combines Individual and Collective Sensing to Trigger Biofilm Dispersal. Curr Biol 2017; 27:3359-3366.e7. [PMID: 29056457 PMCID: PMC5678073 DOI: 10.1016/j.cub.2017.09.041] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Revised: 07/19/2017] [Accepted: 09/19/2017] [Indexed: 01/07/2023]
Abstract
Bacteria can generate benefits for themselves and their kin by living in multicellular, matrix-enclosed communities, termed biofilms, which are fundamental to microbial ecology and the impact bacteria have on the environment, infections, and industry [1, 2, 3, 4, 5, 6]. The advantages of the biofilm mode of life include increased stress resistance and access to concentrated nutrient sources [3, 7, 8]. However, there are also costs associated with biofilm growth, including the metabolic burden of biofilm matrix production, increased resource competition, and limited mobility inside the community [9, 10, 11]. The decision-making strategies used by bacteria to weigh the costs between remaining in a biofilm or actively dispersing are largely unclear, even though the dispersal transition is a central aspect of the biofilm life cycle and critical for infection transmission [12, 13, 14]. Using a combination of genetic and novel single-cell imaging approaches, we show that Vibrio cholerae integrates dual sensory inputs to control the dispersal response: cells use the general stress response, which can be induced via starvation, and they also integrate information about the local cell density and molecular transport conditions in the environment via the quorum sensing apparatus. By combining information from individual (stress response) and collective (quorum sensing) avenues of sensory input, biofilm-dwelling bacteria can make robust decisions to disperse from large biofilms under distress, while preventing premature dispersal when biofilm populations are small. These insights into triggers and regulators of biofilm dispersal are a key step toward actively inducing biofilm dispersal for technological and medical applications, and for environmental control of biofilms. Cells in V. cholerae biofilms decide to disperse by combining two sensory mechanisms Quorum sensing and RpoS provide information on different environmental parameters Integration of both sensory inputs yields robust and optimal dispersal decisions
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Affiliation(s)
- Praveen K Singh
- Max Planck Institute for Terrestrial Microbiology, Karl-von-Frisch-Strasse 10, Marburg 35043, Germany
| | - Sabina Bartalomej
- Max Planck Institute for Terrestrial Microbiology, Karl-von-Frisch-Strasse 10, Marburg 35043, Germany
| | - Raimo Hartmann
- Max Planck Institute for Terrestrial Microbiology, Karl-von-Frisch-Strasse 10, Marburg 35043, Germany
| | - Hannah Jeckel
- Max Planck Institute for Terrestrial Microbiology, Karl-von-Frisch-Strasse 10, Marburg 35043, Germany; Department of Physics, Philipps-Universität Marburg, Renthof 6, Marburg 35032, Germany
| | - Lucia Vidakovic
- Max Planck Institute for Terrestrial Microbiology, Karl-von-Frisch-Strasse 10, Marburg 35043, Germany
| | - Carey D Nadell
- Max Planck Institute for Terrestrial Microbiology, Karl-von-Frisch-Strasse 10, Marburg 35043, Germany
| | - Knut Drescher
- Max Planck Institute for Terrestrial Microbiology, Karl-von-Frisch-Strasse 10, Marburg 35043, Germany; Department of Physics, Philipps-Universität Marburg, Renthof 6, Marburg 35032, Germany.
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31
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Sobe RC, Bond WG, Wotanis CK, Zayner JP, Burriss MA, Fernandez N, Bruger EL, Waters CM, Neufeld HS, Karatan E. Spermine inhibits Vibrio cholerae biofilm formation through the NspS-MbaA polyamine signaling system. J Biol Chem 2017; 292:17025-17036. [PMID: 28827313 PMCID: PMC5641875 DOI: 10.1074/jbc.m117.801068] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Revised: 08/18/2017] [Indexed: 11/06/2022] Open
Abstract
The aquatic bacterium and human intestinal pathogen, Vibrio cholerae, senses and responds to a variety of environment-specific cues to regulate biofilm formation. Specifically, the polyamines norspermidine and spermidine enhance and repress V. cholerae biofilm formation, respectively. These effects are relevant for understanding V. cholerae pathogenicity and are mediated through the periplasmic binding protein NspS and the transmembrane bis-(3'-5') cyclic diguanosine monophosphate (c-di-GMP) phosphodiesterase MbaA. However, the levels of spermidine required to inhibit biofilm formation through this pathway are unlikely to be encountered by V. cholerae in aquatic reservoirs or within the human host during infection. We therefore hypothesized that other polyamines in the gastrointestinal tract may control V. cholerae biofilm formation at physiological levels. The tetramine spermine has been reported to be present at nearly 50 μm concentrations in the intestinal lumen. Here, we report that spermine acts as an exogenous cue that inhibits V. cholerae biofilm formation through the NspS-MbaA signaling system. We found that this effect probably occurs through a direct interaction of spermine with NspS, as purified NspS protein could bind spermine in vitro Spermine also inhibited biofilm formation by altering the transcription of the vps genes involved in biofilm matrix production. Global c-di-GMP levels were unaffected by spermine supplementation, suggesting that biofilm formation may be regulated by variations in local rather than global c-di-GMP pools. Finally, we propose a model illustrating how the NspS-MbaA signaling system may communicate exogenous polyamine content to the cell to control biofilm formation in the aquatic environment and within the human intestine.
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Affiliation(s)
- Richard C Sobe
- From the Department of Biology, Appalachian State University, Boone, North Carolina 28608 and
| | - Whitney G Bond
- From the Department of Biology, Appalachian State University, Boone, North Carolina 28608 and
| | - Caitlin K Wotanis
- From the Department of Biology, Appalachian State University, Boone, North Carolina 28608 and
| | - Josiah P Zayner
- From the Department of Biology, Appalachian State University, Boone, North Carolina 28608 and
| | - Marybeth A Burriss
- From the Department of Biology, Appalachian State University, Boone, North Carolina 28608 and
| | - Nicolas Fernandez
- the Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, Michigan 48824
| | - Eric L Bruger
- the Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, Michigan 48824
| | - Christopher M Waters
- the Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, Michigan 48824
| | - Howard S Neufeld
- From the Department of Biology, Appalachian State University, Boone, North Carolina 28608 and
| | - Ece Karatan
- From the Department of Biology, Appalachian State University, Boone, North Carolina 28608 and
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32
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Genome characterization of two bile-isolated Vibrio fluvialis strains: an insight into pathogenicity and bile salt adaption. Sci Rep 2017; 7:11827. [PMID: 28928424 PMCID: PMC5605694 DOI: 10.1038/s41598-017-12304-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Accepted: 09/06/2017] [Indexed: 12/26/2022] Open
Abstract
Vibrio fluvialis is recognized as an emerging pathogen. However, not much is known about the mechanism of its pathogenesis, and its adaptation to a special niche such as the gall bladder. Here we describe two V. fluvialis strains that cause acute cholecystitis. It is noteworthy that both strains were susceptible to all antibiotics tested, which is in contrast to previous studies, suggesting substantial genetic diversity among V. fluvialis isolates. In agreement with their survival and growth in the gall bladder, the genomes of strains 12605 and 3663 contain a considerable number of genes that confer resistance to bile, including toxR, ompU, tolC, cmeABC, rlpB, yrbK, rpoS, damX and gltK. Furthermore, integrative and conjugative elements (ICEs), virulence factors and prophage regions were also detected in strains 12605 and 3663, reflecting their flexibility in recombination during the evolution of pathogenicity. Comparative analysis of nine available genomes of V. fluvialis revealed a core genome consisting of 3,147 genes. Our results highlight the association of V. fluvialis with a rare disease profile and shed light on the evolution of pathogenesis and niche adaptation of V. fluvialis.
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Abstract
Infectious diseases kill nearly 9 million people annually. Bacterial pathogens are responsible for a large proportion of these diseases, and the bacterial agents of pneumonia, diarrhea, and tuberculosis are leading causes of death and disability worldwide. Increasingly, the crucial role of nonhost environments in the life cycle of bacterial pathogens is being recognized. Heightened scrutiny has been given to the biological processes impacting pathogen dissemination and survival in the natural environment, because these processes are essential for the transmission of pathogenic bacteria to new hosts. This chapter focuses on the model environmental pathogen Vibrio cholerae to describe recent advances in our understanding of how pathogens survive between hosts and to highlight the processes necessary to support the cycle of environmental survival, transmission, and dissemination. We describe the physiological and molecular responses of V. cholerae to changing environmental conditions, focusing on its survival in aquatic reservoirs between hosts and its entry into and exit from human hosts.
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34
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Rossi E, Cimdins A, Lüthje P, Brauner A, Sjöling Å, Landini P, Römling U. "It's a gut feeling" - Escherichia coli biofilm formation in the gastrointestinal tract environment. Crit Rev Microbiol 2017; 44:1-30. [PMID: 28485690 DOI: 10.1080/1040841x.2017.1303660] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Escherichia coli can commonly be found, either as a commensal, probiotic or a pathogen, in the human gastrointestinal (GI) tract. Biofilm formation and its regulation is surprisingly variable, although distinct regulatory pattern of red, dry and rough (rdar) biofilm formation arise in certain pathovars and even clones. In the GI tract, environmental conditions, signals from the host and from commensal bacteria contribute to shape E. coli biofilm formation within the multi-faceted multicellular communities in a complex and integrated fashion. Although some major regulatory networks, adhesion factors and extracellular matrix components constituting E. coli biofilms have been recognized, these processes have mainly been characterized in vitro and in the context of interaction of E. coli strains with intestinal epithelial cells. However, direct observation of E. coli cells in situ, and the vast number of genes encoding surface appendages on the core or accessory genome of E. coli suggests the complexity of the biofilm process to be far from being fully understood. In this review, we summarize biofilm formation mechanisms of commensal, probiotic and pathogenic E. coli in the context of the gastrointestinal tract.
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Affiliation(s)
- Elio Rossi
- a Department of Biosciences , Università degli Studi di Milano , Milan , Italy.,b Novo Nordisk Center for Biosustainabiliy , Technical University of Denmark , Kgs. Lyngby , Denmark
| | - Annika Cimdins
- c Department of Microbiology, Tumor and Cell Biology (MTC) , Karolinska Institutet , Stockholm , Sweden.,d Institute of Hygiene, University of Münster , Münster , Germany
| | - Petra Lüthje
- c Department of Microbiology, Tumor and Cell Biology (MTC) , Karolinska Institutet , Stockholm , Sweden.,e Division of Clinical Microbiology, Department of Laboratory Medicine , Karolinska Institutet and Karolinska University Hospital Huddinge , Stockholm , Sweden
| | - Annelie Brauner
- c Department of Microbiology, Tumor and Cell Biology (MTC) , Karolinska Institutet , Stockholm , Sweden
| | - Åsa Sjöling
- c Department of Microbiology, Tumor and Cell Biology (MTC) , Karolinska Institutet , Stockholm , Sweden
| | - Paolo Landini
- a Department of Biosciences , Università degli Studi di Milano , Milan , Italy
| | - Ute Römling
- c Department of Microbiology, Tumor and Cell Biology (MTC) , Karolinska Institutet , Stockholm , Sweden
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35
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Guilhen C, Forestier C, Balestrino D. Biofilm dispersal: multiple elaborate strategies for dissemination of bacteria with unique properties. Mol Microbiol 2017; 105:188-210. [PMID: 28422332 DOI: 10.1111/mmi.13698] [Citation(s) in RCA: 110] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/15/2017] [Indexed: 01/22/2023]
Abstract
In most environments, microorganisms evolve in a sessile mode of growth, designated as biofilm, which is characterized by cells embedded in a self-produced extracellular matrix. Although a biofilm is commonly described as a "cozy house" where resident bacteria are protected from aggression, bacteria are able to break their biofilm bonds and escape to colonize new environments. This regulated process is observed in a wide variety of species; it is referred to as biofilm dispersal, and is triggered in response to various environmental and biological signals. The first part of this review reports the main regulatory mechanisms and effectors involved in biofilm dispersal. There is some evidence that dispersal is a necessary step between the persistence of bacteria inside biofilm and their dissemination. In the second part, an overview of the main methods used so far to study the dispersal process and to harvest dispersed bacteria was provided. Then focus was on the properties of the biofilm-dispersed bacteria and the fundamental role of the dispersal process in pathogen dissemination within a host organism. In light of the current body of knowledge, it was suggested that dispersal acts as a potent means of disseminating bacteria with enhanced colonization properties in the surrounding environment.
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Affiliation(s)
- Cyril Guilhen
- Laboratoire Microorganismes : Génome et Environnement, UMR CNRS 6023, Université Clermont Auvergne, Clermont Ferrand, F-63001, France
| | - Christiane Forestier
- Laboratoire Microorganismes : Génome et Environnement, UMR CNRS 6023, Université Clermont Auvergne, Clermont Ferrand, F-63001, France
| | - Damien Balestrino
- Laboratoire Microorganismes : Génome et Environnement, UMR CNRS 6023, Université Clermont Auvergne, Clermont Ferrand, F-63001, France
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36
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Survival of the Fittest: How Bacterial Pathogens Utilize Bile To Enhance Infection. Clin Microbiol Rev 2017; 29:819-36. [PMID: 27464994 DOI: 10.1128/cmr.00031-16] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Bacterial pathogens have coevolved with humans in order to efficiently infect, replicate within, and be transmitted to new hosts to ensure survival and a continual infection cycle. For enteric pathogens, the ability to adapt to numerous host factors under the harsh conditions of the gastrointestinal tract is critical for establishing infection. One such host factor readily encountered by enteric bacteria is bile, an innately antimicrobial detergent-like compound essential for digestion and nutrient absorption. Not only have enteric pathogens evolved to resist the bactericidal conditions of bile, but these bacteria also utilize bile as a signal to enhance virulence regulation for efficient infection. This review provides a comprehensive and up-to-date analysis of bile-related research with enteric pathogens. From common responses to the unique expression of specific virulence factors, each pathogen has overcome significant challenges to establish infection in the gastrointestinal tract. Utilization of bile as a signal to modulate virulence factor expression has led to important insights for our understanding of virulence mechanisms for many pathogens. Further research on enteric pathogens exposed to this in vivo signal will benefit therapeutic and vaccine development and ultimately enhance our success at combating such elite pathogens.
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37
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Calcium Enhances Bile Salt-Dependent Virulence Activation in Vibrio cholerae. Infect Immun 2016; 85:IAI.00707-16. [PMID: 27849180 DOI: 10.1128/iai.00707-16] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Accepted: 11/04/2016] [Indexed: 12/17/2022] Open
Abstract
Vibrio cholerae is the causative bacteria of the diarrheal disease cholera, but it also persists in aquatic environments, where it displays an expression profile that is distinct from that during infection. Upon entry into the host, a tightly regulated circuit coordinates the induction of two major virulence factors: cholera toxin and a toxin-coregulated pilus (TCP). It has been shown that a set of bile salts, including taurocholate, serve as host signals to activate V. cholerae virulence through inducing the activity of the transmembrane virulence regulator TcpP. In this study, we investigated the role of calcium, an abundant mental ion in the gut, in the regulation of virulence. We show that whereas Ca2+ alone does not affect virulence, Ca2+ enhances bile salt-dependent virulence activation for V. cholerae The induction of TCP by murine intestinal contents is counteracted when Ca2+ is depleted by the high-affinity calcium chelator EGTA, suggesting that the calcium present in the gut is a relevant signal for V. cholerae virulence induction in vivo We further show that Ca2+ enhances virulence by promoting bile salt-induced TcpP-TcpP interaction. Moreover, fluorescence recovery after photobleaching (FRAP) analysis demonstrated that exposure to bile salts and Ca2+ together decreases the recovery rate for fluorescently labeled TcpP, but not for another inner membrane protein (TatA). Together, these data support a model in which physiological levels of Ca2+ may result in altered bile salt-induced TcpP protein movement and activity, ultimately leading to an increased expression of virulence.
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38
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Dorman CJ, Dorman MJ. DNA supercoiling is a fundamental regulatory principle in the control of bacterial gene expression. Biophys Rev 2016; 8:89-100. [PMID: 28510216 DOI: 10.1007/s12551-016-0238-2] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Accepted: 06/01/2016] [Indexed: 11/28/2022] Open
Abstract
Although it has become routine to consider DNA in terms of its role as a carrier of genetic information, it is also an important contributor to the control of gene expression. This regulatory principle arises from its structural properties. DNA is maintained in an underwound state in most bacterial cells and this has important implications both for DNA storage in the nucleoid and for the expression of genetic information. Underwinding of the DNA through reduction in its linking number potentially imparts energy to the duplex that is available to drive DNA transactions, such as transcription, replication and recombination. The topological state of DNA also influences its affinity for some DNA binding proteins, especially in DNA sequences that have a high A + T base content. The underwinding of DNA by the ATP-dependent topoisomerase DNA gyrase creates a continuum between metabolic flux, DNA topology and gene expression that underpins the global response of the genome to changes in the intracellular and external environments. These connections describe a fundamental and generalised mechanism affecting global gene expression that underlies the specific control of transcription operating through conventional transcription factors. This mechanism also provides a basal level of control for genes acquired by horizontal DNA transfer, assisting microbial evolution, including the evolution of pathogenic bacteria.
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Affiliation(s)
- Charles J Dorman
- Department of Microbiology, Moyne Institute of Preventive Medicine, Trinity College Dublin, Dublin 2, Ireland.
| | - Matthew J Dorman
- Department of Genetics, Smurfit Institute of Genetics, Trinity College Dublin, Dublin 2, Ireland.,Wellcome Trust Sanger Institute, Hinxton, Cambridge, CB10 1SA, UK
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39
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Oladokun MO, Okoh IA. Vibrio cholerae: A historical perspective and current trend. ASIAN PACIFIC JOURNAL OF TROPICAL DISEASE 2016. [DOI: 10.1016/s2222-1808(16)61154-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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40
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Xue Y, Tu F, Shi M, Wu CQ, Ren G, Wang X, Fang W, Song H, Yang M. Redox pathway sensing bile salts activates virulence gene expression in Vibrio cholerae. Mol Microbiol 2016; 102:909-924. [PMID: 27610607 DOI: 10.1111/mmi.13497] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/03/2016] [Indexed: 01/05/2023]
Abstract
Vibrio cholerae, the causative agent of the severe diarrheal disease cholera, has evolved signal transduction systems to control co-ordinately the expression of virulence determinants. It was previously shown that the presence of the bile salts glycocholate and taurocholate in the small intestine causes dimerization of the transmembrane transcription factor TcpP by inducing intermolecular disulphide bonds in the TcpP periplasmic domain. In this study, they further investigated the mechanism of how taurocholate affects V. cholerae virulence determinants. In vitro assay of TcpP oxidation by VcDsbA showed that VcDsbA induced TcpP dimerization in the presence of taurocholate. Taurocholate bound to VcDsbA with a KD of 40 ± 2.5 μM, and also bound other Dsb proteins, including EcDsbA, EcDsbC and VcDsbC. Taurocholate inhibited VcDsbA reductase activity without affecting VcDsbA secondary structure or thermostability. VcDsbA and its substrates were more extensively reduced in the presence of taurocholate, as compared with their redox state in the absence of taurocholate. The data presented here not only provide new insights into the mechanism by which bile salts induce V. cholerae virulence but also suggest a means by which to develop inhibitors against DsbA.
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Affiliation(s)
- Yuanyuan Xue
- College of Animal Science & Technology, China-Australia Joint-Laboratory for Animal Health Big Data Analytics, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection & Internet Technology, Zhejiang A&F University, Lin'an 311300, Zhejiang Province, China
| | - Fei Tu
- College of Animal Science & Technology, China-Australia Joint-Laboratory for Animal Health Big Data Analytics, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection & Internet Technology, Zhejiang A&F University, Lin'an 311300, Zhejiang Province, China
| | - Mengting Shi
- College of Animal Science & Technology, China-Australia Joint-Laboratory for Animal Health Big Data Analytics, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection & Internet Technology, Zhejiang A&F University, Lin'an 311300, Zhejiang Province, China
| | - Chun-Qin Wu
- College of Animal Science & Technology, China-Australia Joint-Laboratory for Animal Health Big Data Analytics, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection & Internet Technology, Zhejiang A&F University, Lin'an 311300, Zhejiang Province, China.,Department of Animal Science, Wenzhou Vocational College of Science and Technology, Wenzhou, Zhejiang, China
| | - Guoping Ren
- New England Biolabs Inc, Ipswich, Massachusetts, USA
| | - Xiaojie Wang
- College of Animal Science & Technology, China-Australia Joint-Laboratory for Animal Health Big Data Analytics, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection & Internet Technology, Zhejiang A&F University, Lin'an 311300, Zhejiang Province, China
| | - Weihuan Fang
- Institute of Preventive Veterinary Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Houhui Song
- College of Animal Science & Technology, China-Australia Joint-Laboratory for Animal Health Big Data Analytics, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection & Internet Technology, Zhejiang A&F University, Lin'an 311300, Zhejiang Province, China
| | - Menghua Yang
- College of Animal Science & Technology, China-Australia Joint-Laboratory for Animal Health Big Data Analytics, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection & Internet Technology, Zhejiang A&F University, Lin'an 311300, Zhejiang Province, China
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DNA supercoiling is a fundamental regulatory principle in the control of bacterial gene expression. Biophys Rev 2016; 8:209-220. [PMID: 28510224 DOI: 10.1007/s12551-016-0205-y] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Accepted: 06/01/2016] [Indexed: 12/27/2022] Open
Abstract
Although it has become routine to consider DNA in terms of its role as a carrier of genetic information, it is also an important contributor to the control of gene expression. This regulatory principle arises from its structural properties. DNA is maintained in an underwound state in most bacterial cells and this has important implications both for DNA storage in the nucleoid and for the expression of genetic information. Underwinding of the DNA through reduction in its linking number potentially imparts energy to the duplex that is available to drive DNA transactions, such as transcription, replication and recombination. The topological state of DNA also influences its affinity for some DNA binding proteins, especially in DNA sequences that have a high A + T base content. The underwinding of DNA by the ATP-dependent topoisomerase DNA gyrase creates a continuum between metabolic flux, DNA topology and gene expression that underpins the global response of the genome to changes in the intracellular and external environments. These connections describe a fundamental and generalised mechanism affecting global gene expression that underlies the specific control of transcription operating through conventional transcription factors. This mechanism also provides a basal level of control for genes acquired by horizontal DNA transfer, assisting microbial evolution, including the evolution of pathogenic bacteria.
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42
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Almada AA, Tarrant AM. Vibrio elicits targeted transcriptional responses from copepod hosts. FEMS Microbiol Ecol 2016; 92:fiw072. [DOI: 10.1093/femsec/fiw072] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/04/2016] [Indexed: 11/15/2022] Open
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Biofilm Formation and Detachment in Gram-Negative Pathogens Is Modulated by Select Bile Acids. PLoS One 2016; 11:e0149603. [PMID: 26992172 PMCID: PMC4798295 DOI: 10.1371/journal.pone.0149603] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Accepted: 02/03/2016] [Indexed: 11/19/2022] Open
Abstract
Biofilms are a ubiquitous feature of microbial community structure in both natural and host environments; they enhance transmission and infectivity of pathogens and provide protection from human defense mechanisms and antibiotics. However, few natural products are known that impact biofilm formation or persistence for either environmental or pathogenic bacteria. Using the combination of a novel natural products library from the fish microbiome and an image-based screen for biofilm inhibition, we describe the identification of taurine-conjugated bile acids as inhibitors of biofilm formation against both Vibrio cholerae and Pseudomonas aeruginosa. Taurocholic acid (1) was isolated from the fermentation broth of the fish microbiome-derived strain of Rhodococcus erythropolis and identified using standard NMR and MS methods. Screening of the twelve predominant human steroidal bile acid components revealed that a subset of these compounds can inhibit biofilm formation, induce detachment of preformed biofilms under static conditions, and that these compounds display distinct structure-activity relationships against V. cholerae and P. aeruginosa. Our findings highlight the significance of distinct bile acid components in the regulation of biofilm formation and dispersion in two different clinically relevant bacterial pathogens, and suggest that the bile acids, which are endogenous mammalian metabolites used to solubilize dietary fats, may also play a role in maintaining host health against bacterial infection.
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Abstract
Vibrio cholerae can switch between motile and biofilm lifestyles. The last decades have been marked by a remarkable increase in our knowledge of the structure, regulation, and function of biofilms formed under laboratory conditions. Evidence has grown suggesting that V. cholerae can form biofilm-like aggregates during infection that could play a critical role in pathogenesis and disease transmission. However, the structure and regulation of biofilms formed during infection, as well as their role in intestinal colonization and virulence, remains poorly understood. Here, we review (i) the evidence for biofilm formation during infection, (ii) the coordinate regulation of biofilm and virulence gene expression, and (iii) the host signals that favor V. cholerae transitions between alternative lifestyles during intestinal colonization, and (iv) we discuss a model for the role of V. cholerae biofilms in pathogenicity.
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Petrova OE, Sauer K. Escaping the biofilm in more than one way: desorption, detachment or dispersion. Curr Opin Microbiol 2016; 30:67-78. [PMID: 26826978 DOI: 10.1016/j.mib.2016.01.004] [Citation(s) in RCA: 151] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2015] [Revised: 01/07/2016] [Accepted: 01/08/2016] [Indexed: 12/15/2022]
Abstract
Biofilm bacteria have developed escape strategies to avoid stresses associated with biofilm growth, respond to changing environmental conditions, and disseminate to new locations. An ever-expanding body of research suggests that cellular release from biofilms is distinct from a simple reversal of attachment and reversion to a planktonic mode of growth, with biofilm dispersion involving sensing of specific cues, regulatory signal transduction, and consequent physiological alterations. However, dispersion is only one of many ways to escape the biofilm mode of growth. The present review is aimed at distinguishing this active and regulated process of dispersion from the passive processes of desorption and detachment by highlighting the regulatory processes and distinct phenotypes specific to dispersed cells.
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Affiliation(s)
- Olga E Petrova
- Department of Biological Sciences, Binghamton Biofilm Research Center, Binghamton University, Binghamton, NY 13902, United States
| | - Karin Sauer
- Department of Biological Sciences, Binghamton Biofilm Research Center, Binghamton University, Binghamton, NY 13902, United States.
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Hay AJ, Zhu J. In Sickness and in Health: The Relationships Between Bacteria and Bile in the Human Gut. ADVANCES IN APPLIED MICROBIOLOGY 2016; 96:43-64. [PMID: 27565580 DOI: 10.1016/bs.aambs.2016.07.019] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Colonization of a human host with a commensal microbiota has a complex interaction in which bacterial communities provide numerous health benefits to the host. An equilibrium between host and microbiota is kept in check with the help of biliary secretions by the host. Bile, composed primarily of bile salts, promotes digestion. It also provides a barrier between host and bacteria. After bile salts are synthesized in the liver, they are stored in the gallbladder to be released after food intake. The set of host-secreted bile salts is modified by the resident bacteria. Because bile salts are toxic to bacteria, an equilibrium of modified bile salts is reached that allows commensal bacteria to survive, yet rebuffs invading pathogens. In addition to direct toxic effects on cells, bile salts maintain homeostasis as signaling molecules, tuning the immune system. To cause disease, gram-negative pathogenic bacteria have shared strategies to survive this harsh environment. Through exclusion of bile, efflux of bile, and repair of bile-induced damage, these pathogens can successfully disrupt and outcompete the microbiota to activate virulence factors.
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Affiliation(s)
- A J Hay
- University of Pennsylvania, Philadelphia, PA, United States
| | - J Zhu
- University of Pennsylvania, Philadelphia, PA, United States
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Bachmann V, Kostiuk B, Unterweger D, Diaz-Satizabal L, Ogg S, Pukatzki S. Bile Salts Modulate the Mucin-Activated Type VI Secretion System of Pandemic Vibrio cholerae. PLoS Negl Trop Dis 2015; 9:e0004031. [PMID: 26317760 PMCID: PMC4552747 DOI: 10.1371/journal.pntd.0004031] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2015] [Accepted: 08/04/2015] [Indexed: 01/18/2023] Open
Abstract
The causative agent of cholera, Vibrio cholerae, regulates its diverse virulence factors to thrive in the human small intestine and environmental reservoirs. Among this pathogen’s arsenal of virulence factors is the tightly regulated type VI secretion system (T6SS). This system acts as an inverted bacteriophage to inject toxins into competing bacteria and eukaryotic phagocytes. V. cholerae strains responsible for the current 7th pandemic activate their T6SS within the host. We established that T6SS-mediated competition occurs upon T6SS activation in the infant mouse, and that this system is functional under anaerobic conditions. When investigating the intestinal host factors mucins (a glycoprotein component of mucus) and bile for potential regulatory roles in controlling the T6SS, we discovered that once mucins activate the T6SS, bile acids can further modulate T6SS activity. Microbiota modify bile acids to inhibit T6SS-mediated killing of commensal bacteria. This interplay is a novel interaction between commensal bacteria, host factors, and the V. cholerae T6SS, showing an active host role in infection. The type six-secretion system (T6SS) is a molecular syringe that many Gram-negative pathogens use to kill other bacteria, including commensal bacteria of the human gut. We investigated how the environment of the intestine, specifically commensal bacteria, the mucus lining, and bile affect the T6SS of the bacterial pathogen Vibrio cholerae. First, we showed that the mucins, a family of proteins ubiquitously found in the intestine, activate the T6SS thereby allowing V. cholerae to kill other bacteria. Second, we showed that the magnitude of killing is regulated by bile acids. Certain bile acids produced by the host decrease the killing of bacteria by the V. cholerae T6SS. Last, we demonstrated that prominent members of the host microbiota metabolize these bile acids that enhance bacterial killing by V. cholerae into bile acids that diminish the bacterial killing effects of the T6SS. Our study suggests that the gut microbiota is an important first line of defense against bacterial pathogens, and that this line of defense may be impaired in individuals in poor health. Promoting a healthy microbial environment in the gut could play a role in counteracting cholera by reducing the ability of Vibrio cholerae to compete in the gut.
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Affiliation(s)
- Verena Bachmann
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada
| | - Benjamin Kostiuk
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada
| | - Daniel Unterweger
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada
| | - Laura Diaz-Satizabal
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada
| | - Stephen Ogg
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada
| | - Stefan Pukatzki
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada
- * E-mail:
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Abstract
To cause the diarrheal disease cholera, Vibrio cholerae must effectively colonize the small intestine. In order to do so, the bacterium needs to successfully travel through the stomach and withstand the presence of agents such as bile and antimicrobial peptides in the intestinal lumen and mucus. The bacterial cells penetrate the viscous mucus layer covering the epithelium and attach and proliferate on its surface. In this review, we discuss recent developments and known aspects of the early stages of V. cholerae intestinal colonization and highlight areas that remain to be fully understood. We propose mechanisms and postulate a model that covers some of the steps that are required in order for the bacterium to efficiently colonize the human host. A deeper understanding of the colonization dynamics of V. cholerae and other intestinal pathogens will provide us with a variety of novel targets and strategies to avoid the diseases caused by these organisms.
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Affiliation(s)
- Salvador Almagro-Moreno
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, United States of America
- * E-mail:
| | - Kali Pruss
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, United States of America
| | - Ronald K. Taylor
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, United States of America
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Teschler JK, Zamorano-Sánchez D, Utada AS, Warner CJA, Wong GCL, Linington RG, Yildiz FH. Living in the matrix: assembly and control of Vibrio cholerae biofilms. Nat Rev Microbiol 2015; 13:255-68. [PMID: 25895940 PMCID: PMC4437738 DOI: 10.1038/nrmicro3433] [Citation(s) in RCA: 260] [Impact Index Per Article: 28.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Nearly all bacteria form biofilms as a strategy for survival and persistence. Biofilms are associated with biotic and abiotic surfaces and are composed of aggregates of cells that are encased by a self-produced or acquired extracellular matrix. Vibrio cholerae has been studied as a model organism for understanding biofilm formation in environmental pathogens, as it spends much of its life cycle outside of the human host in the aquatic environment. Given the important role of biofilm formation in the V. cholerae life cycle, the molecular mechanisms underlying this process and the signals that trigger biofilm assembly or dispersal have been areas of intense investigation over the past 20 years. In this Review, we discuss V. cholerae surface attachment, various matrix components and the regulatory networks controlling biofilm formation.
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Affiliation(s)
- Jennifer K. Teschler
- Department of Microbiology and Environmental Toxicology, University of California Santa Cruz, Santa Cruz, CA 95064, USA
| | - David Zamorano-Sánchez
- Department of Microbiology and Environmental Toxicology, University of California Santa Cruz, Santa Cruz, CA 95064, USA
| | - Andrew S. Utada
- Bioengineering Department, Chemistry and Biochemistry Department, and NanoSystems Institute, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Christopher J. A. Warner
- Department of Chemistry and Biochemistry, University of California Santa Cruz, Santa Cruz, CA 95064, USA
| | - Gerard C. L. Wong
- Bioengineering Department, Chemistry and Biochemistry Department, and NanoSystems Institute, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Roger G. Linington
- Department of Chemistry and Biochemistry, University of California Santa Cruz, Santa Cruz, CA 95064, USA
| | - Fitnat H. Yildiz
- Department of Microbiology and Environmental Toxicology, University of California Santa Cruz, Santa Cruz, CA 95064, USA
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50
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Vibrio cholerae represses polysaccharide synthesis to promote motility in mucosa. Infect Immun 2015; 83:1114-21. [PMID: 25561707 DOI: 10.1128/iai.02841-14] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
The viscoelastic mucus layer of gastrointestinal tracts is a host defense barrier that a successful enteric pathogen, such as Vibrio cholerae, must circumvent. V. cholerae, the causative agent of cholera, is able to penetrate the mucosa and colonize the epithelial surface of the small intestine. In this study, we found that mucin, the major component of mucus, promoted V. cholerae movement on semisolid medium and in liquid medium. A genome-wide screen revealed that Vibrio polysaccharide (VPS) production was inversely correlated with mucin-enhanced motility. Mucin adhesion assays indicated that VPS bound to mucin. Moreover, we found that vps expression was reduced upon exposure to mucin. In an infant mouse colonization model, mutants that overexpressed VPS colonized less effectively than wild-type strains in more distal intestinal regions. These results suggest that V. cholerae is able to sense mucosal signals and modulate vps expression accordingly so as to promote fast motion in mucus, thus allowing for rapid spread throughout the intestines.
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