1
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Pauzé-Foixet J, Mathieu-Denoncourt A, Duperthuy M. Elevated concentrations of polymyxin B elicit a biofilm-specific resistance mechanism in Vibrio cholerae. Res Microbiol 2024; 175:104179. [PMID: 38185395 DOI: 10.1016/j.resmic.2023.104179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Revised: 12/05/2023] [Accepted: 12/30/2023] [Indexed: 01/09/2024]
Abstract
Vibrio cholerae can form biofilms in the aquatic environment and in the human intestine, facilitating the release of hyper-infectious aggregates. Due to the increasing antibiotic resistance, alternatives need to be found. One of these alternatives is antimicrobial peptides, including polymyxin B (PmB). In this study, we first investigated the resistance of V. cholerae O1 El Tor strain A1552 to various antimicrobials under aerobic and anaerobic conditions. An increased resistance to PmB is observed in anaerobiosis, with a 3-fold increase in the dose required for 50 % growth inhibition. We then studied the impact of the PmB on the formation and the degradation of V. cholerae biofilms to PmB. Our results show that PmB affects more efficiently biofilm formation under anaerobic conditions. On the other hand, preformed biofilms are susceptible to degradation by PmB at concentrations close to the minimal inhibitory concentration. At higher concentrations, we observe an opacification of the biofilm structures within 20 min post-treatment, suggesting a densification of the structure. This densification does not seem to result from the overexpression of matrix genes but rather from DNA release through massive cell lysis, likely forming a protective shield that limits the penetration of the PmB into the biofilm.
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Affiliation(s)
- Julien Pauzé-Foixet
- Département de Microbiologie, Infectiologie et Immunologie, Faculté de médecine, Université de Montréal, Montréal, Québec, Canada
| | - Annabelle Mathieu-Denoncourt
- Département de Microbiologie, Infectiologie et Immunologie, Faculté de médecine, Université de Montréal, Montréal, Québec, Canada
| | - Marylise Duperthuy
- Département de Microbiologie, Infectiologie et Immunologie, Faculté de médecine, Université de Montréal, Montréal, Québec, Canada.
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2
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Ng KM, Pannu S, Liu S, Burckhardt JC, Hughes T, Van Treuren W, Nguyen J, Naqvi K, Nguyen B, Clayton CA, Pepin DM, Collins SR, Tropini C. Single-strain behavior predicts responses to environmental pH and osmolality in the gut microbiota. mBio 2023; 14:e0075323. [PMID: 37432034 PMCID: PMC10470613 DOI: 10.1128/mbio.00753-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Accepted: 05/23/2023] [Indexed: 07/12/2023] Open
Abstract
Changes to gut environmental factors such as pH and osmolality due to disease or drugs correlate with major shifts in microbiome composition; however, we currently cannot predict which species can tolerate such changes or how the community will be affected. Here, we assessed the growth of 92 representative human gut bacterial strains spanning 28 families across multiple pH values and osmolalities in vitro. The ability to grow in extreme pH or osmolality conditions correlated with the availability of known stress response genes in many cases, but not all, indicating that novel pathways may participate in protecting against acid or osmotic stresses. Machine learning analysis uncovered genes or subsystems that are predictive of differential tolerance in either acid or osmotic stress. For osmotic stress, we corroborated the increased abundance of these genes in vivo during osmotic perturbation. The growth of specific taxa in limiting conditions in isolation in vitro correlated with survival in complex communities in vitro and in an in vivo mouse model of diet-induced intestinal acidification. Our data show that in vitro stress tolerance results are generalizable and that physical parameters may supersede interspecies interactions in determining the relative abundance of community members. This study provides insight into the ability of the microbiota to respond to common perturbations that may be encountered in the gut and provides a list of genes that correlate with increased ability to survive in these conditions. IMPORTANCE To achieve greater predictability in microbiota studies, it is crucial to consider physical environmental factors such as pH and particle concentration, as they play a pivotal role in influencing bacterial function and survival. For example, pH is significantly altered in various diseases, including cancers, inflammatory bowel disease, as well in the case of over-the-counter drug use. Additionally, conditions like malabsorption can affect particle concentration. In our study, we investigate how changes in environmental pH and osmolality can serve as predictive indicators of bacterial growth and abundance. Our research provides a comprehensive resource for anticipating shifts in microbial composition and gene abundance during complex perturbations. Moreover, our findings underscore the significance of the physical environment as a major driver of bacterial composition. Finally, this work emphasizes the necessity of incorporating physical measurements into animal and clinical studies to better understand the factors influencing shifts in microbiota abundance.
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Affiliation(s)
- Katharine M. Ng
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, Canada
- School of Biomedical Engineering, University of British Columbia, Vancouver, Canada
| | - Sagar Pannu
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, Canada
| | - Sijie Liu
- School of Biomedical Engineering, University of British Columbia, Vancouver, Canada
| | - Juan C. Burckhardt
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, Canada
| | - Thad Hughes
- Independent Researcher, Vancouver, British Columbia, Canada
| | - Will Van Treuren
- Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, California, USA
| | - Jen Nguyen
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, Canada
| | - Kisa Naqvi
- School of Biomedical Engineering, University of British Columbia, Vancouver, Canada
| | - Bachviet Nguyen
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, Canada
| | - Charlotte A. Clayton
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, Canada
| | - Deanna M. Pepin
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, Canada
| | - Samuel R. Collins
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, Canada
| | - Carolina Tropini
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, Canada
- School of Biomedical Engineering, University of British Columbia, Vancouver, Canada
- Humans and the Microbiome Program, Canadian Institute for Advanced Research, Toronto, Canada
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3
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Coppens L, Tschirhart T, Leary DH, Colston SM, Compton JR, Hervey WJ, Dana KL, Vora GJ, Bordel S, Ledesma-Amaro R. Vibrio natriegens genome-scale modeling reveals insights into halophilic adaptations and resource allocation. Mol Syst Biol 2023; 19:e10523. [PMID: 36847213 PMCID: PMC10090949 DOI: 10.15252/msb.202110523] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 02/07/2023] [Accepted: 02/09/2023] [Indexed: 03/01/2023] Open
Abstract
Vibrio natriegens is a Gram-negative bacterium with an exceptional growth rate that has the potential to become a standard biotechnological host for laboratory and industrial bioproduction. Despite this burgeoning interest, the current lack of organism-specific qualitative and quantitative computational tools has hampered the community's ability to rationally engineer this bacterium. In this study, we present the first genome-scale metabolic model (GSMM) of V. natriegens. The GSMM (iLC858) was developed using an automated draft assembly and extensive manual curation and was validated by comparing predicted yields, central metabolic fluxes, viable carbon substrates, and essential genes with empirical data. Mass spectrometry-based proteomics data confirmed the translation of at least 76% of the enzyme-encoding genes predicted to be expressed by the model during aerobic growth in a minimal medium. iLC858 was subsequently used to carry out a metabolic comparison between the model organism Escherichia coli and V. natriegens, leading to an analysis of the model architecture of V. natriegens' respiratory and ATP-generating system and the discovery of a role for a sodium-dependent oxaloacetate decarboxylase pump. The proteomics data were further used to investigate additional halophilic adaptations of V. natriegens. Finally, iLC858 was utilized to create a Resource Balance Analysis model to study the allocation of carbon resources. Taken together, the models presented provide useful computational tools to guide metabolic engineering efforts in V. natriegens.
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Affiliation(s)
- Lucas Coppens
- Department of Bioengineering and Imperial College Centre for Synthetic Biology, Imperial College London, London, UK
| | - Tanya Tschirhart
- US Naval Research Laboratory, Center for Bio/Molecular Science and Engineering, Washington, DC, USA
| | - Dagmar H Leary
- US Naval Research Laboratory, Center for Bio/Molecular Science and Engineering, Washington, DC, USA
| | - Sophie M Colston
- US Naval Research Laboratory, Center for Bio/Molecular Science and Engineering, Washington, DC, USA
| | - Jaimee R Compton
- US Naval Research Laboratory, Center for Bio/Molecular Science and Engineering, Washington, DC, USA
| | - William Judson Hervey
- US Naval Research Laboratory, Center for Bio/Molecular Science and Engineering, Washington, DC, USA
| | | | - Gary J Vora
- US Naval Research Laboratory, Center for Bio/Molecular Science and Engineering, Washington, DC, USA
| | - Sergio Bordel
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Valladolid, Spain
| | - Rodrigo Ledesma-Amaro
- Department of Bioengineering and Imperial College Centre for Synthetic Biology, Imperial College London, London, UK
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4
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Insights into the chemistry of the amphibactin-metal (M 3+) interaction and its role in antibiotic resistance. Sci Rep 2020; 10:21049. [PMID: 33273481 PMCID: PMC7712776 DOI: 10.1038/s41598-020-77807-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Accepted: 11/05/2020] [Indexed: 12/03/2022] Open
Abstract
We have studied the diversity and specificity of interactions of amphibactin produced by Vibrio genus bacterium (Vibrio sp. HC0601C5) with iron and various metal ions in + 3 oxidation state in an octahedral (Oh) environment. To survive in the iron-deficient environment of their host, pathogenic bacteria have devised various efficient iron acquisition strategies. One such strategy involves the production of low molecular weight peptides called siderophores, which have a strong affinity and specificity to chelate Fe3+ and can thus facilitate uptake of this metal in order to ensure iron requirements. The Fe uptake by amphibactin and the release of iron inside the cell have been studied. Comparison of the interaction of different transition metal ions (M3+) with amphibactin has been studied and it reveals that Co and Ga form stable complexes with this siderophore. The competition of Co and Ga with Fe impedes iron uptake by bacteria, thereby preventing infection.
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5
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Peschek N, Herzog R, Singh PK, Sprenger M, Meyer F, Fröhlich KS, Schröger L, Bramkamp M, Drescher K, Papenfort K. RNA-mediated control of cell shape modulates antibiotic resistance in Vibrio cholerae. Nat Commun 2020; 11:6067. [PMID: 33247102 PMCID: PMC7695739 DOI: 10.1038/s41467-020-19890-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Accepted: 11/06/2020] [Indexed: 02/06/2023] Open
Abstract
Vibrio cholerae, the cause of cholera disease, exhibits a characteristic curved rod morphology, which promotes infectivity and motility in dense hydrogels. Periplasmic protein CrvA determines cell curvature in V. cholerae, yet the regulatory factors controlling CrvA are unknown. Here, we discover the VadR small RNA (sRNA) as a post-transcriptional inhibitor of the crvA mRNA. Mutation of vadR increases cell curvature, whereas overexpression has the inverse effect. We show that vadR transcription is activated by the VxrAB two-component system and triggered by cell-wall-targeting antibiotics. V. cholerae cells failing to repress crvA by VadR display decreased survival upon challenge with penicillin G indicating that cell shape maintenance by the sRNA is critical for antibiotic resistance. VadR also blocks the expression of various key biofilm genes and thereby inhibits biofilm formation in V. cholerae. Thus, VadR is an important regulator for synchronizing peptidoglycan integrity, cell shape, and biofilm formation in V. cholerae.
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Affiliation(s)
- Nikolai Peschek
- Institute of Microbiology, Friedrich Schiller University, 07745, Jena, Germany
- Faculty of Biology, Ludwig-Maximilians-University of Munich, 82152, Martinsried, Germany
| | - Roman Herzog
- Institute of Microbiology, Friedrich Schiller University, 07745, Jena, Germany
- Faculty of Biology, Ludwig-Maximilians-University of Munich, 82152, Martinsried, Germany
| | - Praveen K Singh
- Max Planck Institute for Terrestrial Microbiology, 35043, Marburg, Germany
| | - Marcel Sprenger
- Institute of Microbiology, Friedrich Schiller University, 07745, Jena, Germany
| | - Fabian Meyer
- Faculty of Biology, Ludwig-Maximilians-University of Munich, 82152, Martinsried, Germany
- Institute for General Microbiology, Christian-Albrechts-University, Kiel, Germany
| | - Kathrin S Fröhlich
- Institute of Microbiology, Friedrich Schiller University, 07745, Jena, Germany
- Faculty of Biology, Ludwig-Maximilians-University of Munich, 82152, Martinsried, Germany
- Microverse Cluster, Friedrich Schiller University Jena, 07743, Jena, Germany
| | - Luise Schröger
- Faculty of Biology, Ludwig-Maximilians-University of Munich, 82152, Martinsried, Germany
| | - Marc Bramkamp
- Faculty of Biology, Ludwig-Maximilians-University of Munich, 82152, Martinsried, Germany
- Institute for General Microbiology, Christian-Albrechts-University, Kiel, Germany
| | - Knut Drescher
- Max Planck Institute for Terrestrial Microbiology, 35043, Marburg, Germany
- Department of Physics, Philipps-Universität Marburg, 35032, Marburg, Germany
| | - Kai Papenfort
- Institute of Microbiology, Friedrich Schiller University, 07745, Jena, Germany.
- Faculty of Biology, Ludwig-Maximilians-University of Munich, 82152, Martinsried, Germany.
- Microverse Cluster, Friedrich Schiller University Jena, 07743, Jena, Germany.
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6
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Bueno E, Sit B, Waldor MK, Cava F. Genetic Dissection of the Fermentative and Respiratory Contributions Supporting Vibrio cholerae Hypoxic Growth. J Bacteriol 2020; 202:e00243-20. [PMID: 32631948 PMCID: PMC7685561 DOI: 10.1128/jb.00243-20] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2020] [Accepted: 06/29/2020] [Indexed: 11/20/2022] Open
Abstract
Both fermentative and respiratory processes contribute to bacterial metabolic adaptations to low oxygen tension (hypoxia). In the absence of O2 as a respiratory electron sink, many bacteria utilize alternative electron acceptors, such as nitrate (NO3-). During canonical NO3- respiration, NO3- is reduced in a stepwise manner to N2 by a dedicated set of reductases. Vibrio cholerae, the etiological agent of cholera, requires only a single periplasmic NO3- reductase (NapA) to undergo NO3- respiration, suggesting that the pathogen possesses a noncanonical NO3- respiratory chain. In this study, we used complementary transposon-based screens to identify genetic determinants of general hypoxic growth and NO3- respiration in V. cholerae We found that while the V. cholerae NO3- respiratory chain is primarily composed of homologues of established NO3- respiratory genes, it also includes components previously unlinked to this process, such as the Na+-NADH dehydrogenase Nqr. The ethanol-generating enzyme AdhE was shown to be the principal fermentative branch required during hypoxic growth in V. cholerae Relative to single adhE or napA mutant strains, a V. cholerae strain lacking both genes exhibited severely impaired hypoxic growth in vitro and in vivo Our findings reveal the genetic basis of a specific interaction between disparate energy production pathways that supports pathogen fitness under shifting conditions. Such metabolic specializations in V. cholerae and other pathogens are potential targets for antimicrobial interventions.IMPORTANCE Bacteria reprogram their metabolism in environments with low oxygen levels (hypoxia). Typically, this occurs via regulation of two major, but largely independent, metabolic pathways: fermentation and respiration. In this study, we found that the diarrheal pathogen Vibrio cholerae has a respiratory chain for NO3- that consists largely of components found in other NO3- respiratory systems but also contains several proteins not previously linked to this process. Both AdhE-dependent fermentation and NO3- respiration were required for efficient pathogen growth under both laboratory conditions and in an animal infection model. These observations provide a specific example of fermentative respiratory interactions and identify metabolic vulnerabilities that may be targetable for new antimicrobial agents in V. cholerae and related pathogens.
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Affiliation(s)
- Emilio Bueno
- Laboratory for Molecular Infection Medicine Sweden, Department of Molecular Biology, Umeå Center for Microbial Research, Umeå University, Umeå, Sweden
| | - Brandon Sit
- Department of Microbiology, Harvard Medical School, Boston, Massachusetts, USA
- Division of Infectious Diseases, Brigham and Women's Hospital, Boston, Massachusetts, USA
| | - Matthew K Waldor
- Department of Microbiology, Harvard Medical School, Boston, Massachusetts, USA
- Division of Infectious Diseases, Brigham and Women's Hospital, Boston, Massachusetts, USA
- Howard Hughes Medical Institute, Boston, Massachusetts, USA
| | - Felipe Cava
- Laboratory for Molecular Infection Medicine Sweden, Department of Molecular Biology, Umeå Center for Microbial Research, Umeå University, Umeå, Sweden
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7
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Abstract
The Na+-NQR complex functions as a unique redox-driven sodium pump, generating membrane potential directly. However, whether it mediates generation of membrane potential indirectly is unknown. The present study shows that the Na+-NQR complex impacts membrane potential through other antiporter families Atp and Mnh. It proceeds by ATP and then cAMP/CRP regulon, which inhibits l-alanine catabolism and promotes l-alanine anabolism. When the Na+-NQR complex is reduced as in antibiotic-resistant bacteria, l-alanine is depressed, which is related to the antibiotic resistance phenotypes. However, exogenous l-alanine reverts the phenotype and promotes antibiotic-mediated killing. These findings suggest a novel mechanism by which the Na+-NQR system regulates antibiotic resistance via l-alanine metabolism in a cAMP/CRP complex-dependent manner. Sodium-translocating NADH:quinone oxidoreductase (Na+-NQR) functions as a unique redox-driven sodium pump, generating membrane potential, which is related to aminoglycoside antibiotic resistance. However, whether it modulates other metabolisms to confer antibiotic resistance is unknown. The present study showed that loss of nqrA or nqrF led to differential metabolomes with elevated resistance to aminoglycoside antibiotics. Decreased alanine, aspartate, and glutamate metabolism and depressed abundance of alanine were characterized as the most impacted pathway and crucial biomarker, respectively. Further data showed that higher viability was detected in ΔnqrA and ΔnqrF mutant strains than their parent strain ATCC 33787 in the presence of gentamicin but recovered by exogenous l-alanine. It proceeds by the following events. The loss of nqrA or nqrF led to the decrease of membrane potential, ATPase activity, and then ATP and cyclic AMP (cAMP), which reduced the cAMP/CRP (cAMP receptor protein) complex. The reduced cAMP/CRP complex promoted l-alanine catabolism and inhibited l-alanine anabolism, causing reduced levels of alanine. Reduced alanine affected the expression of antiporter families Atp and Mnh genes. Our results suggest a novel mechanism by which the Na+-NQR system regulates antibiotic resistance via l-alanine metabolism in a cAMP/CRP complex-dependent manner.
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8
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Moradali MF, Ghods S, Angelini TE, Davey ME. Amino acids as wetting agents: surface translocation by Porphyromonas gingivalis. THE ISME JOURNAL 2019; 13:1560-1574. [PMID: 30783212 PMCID: PMC6775972 DOI: 10.1038/s41396-019-0360-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Revised: 01/11/2019] [Accepted: 01/17/2019] [Indexed: 02/06/2023]
Abstract
Our understanding of how oral microbiota adapt in response to changes in their surroundings remains limited. This is particularly true of the slow-growing anaerobes that persist below the gum line. Here, we report that the oral anaerobe Porphyromonas gingivalis strain 381 can surface translocate when sandwiched between two surfaces. We show that during movement, this bacterium alters its metabolism, specifically side products of arginine utilization including citrulline and ornithine accumulated in the translocating cells; while arginine, N-acetyl-arginine, and the polyamine putrescine, which is produced from arginine were consumed. In addition, our results indicate that movement requires modification of the surrounding environment via proteolysis, cell dispersion, cell-on-cell rolling, and sub-diffusive cell-driven motility. We also show that production of fimbriae and fimbriae-associated proteins; as well as the regulation of contact-dependent growth inhibition genes, which are known to be involved in self-nonself discrimination, and the type IX secretion system are central to surface translocation. These studies provide a first glimpse into P. gingivalis motility and its relationship to ecological variables.
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Affiliation(s)
- M Fata Moradali
- Department of Oral Biology, College of Dentistry, University of Florida, Gainesville, FL, 32610, USA
| | - Shirin Ghods
- Department of Oral Biology, College of Dentistry, University of Florida, Gainesville, FL, 32610, USA
| | - Thomas E Angelini
- Department of Mechanical & Aerospace Engineering, University of Florida, Gainesville, FL, 32610, USA
| | - Mary Ellen Davey
- Department of Oral Biology, College of Dentistry, University of Florida, Gainesville, FL, 32610, USA.
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9
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Denis K, Le Bris M, Le Guennec L, Barnier JP, Faure C, Gouge A, Bouzinba-Ségard H, Jamet A, Euphrasie D, Durel B, Barois N, Pelissier P, Morand PC, Coureuil M, Lafont F, Join-Lambert O, Nassif X, Bourdoulous S. Targeting Type IV pili as an antivirulence strategy against invasive meningococcal disease. Nat Microbiol 2019; 4:972-984. [PMID: 30911127 DOI: 10.1038/s41564-019-0395-8] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Accepted: 01/30/2019] [Indexed: 11/09/2022]
Abstract
Bacterial virulence factors are attractive targets for the development of therapeutics. Type IV pili, which are associated with a remarkable array of properties including motility, the interaction between bacteria and attachment to biotic and abiotic surfaces, represent particularly appealing virulence factor targets. Type IV pili are present in numerous bacterial species and are critical for their pathogenesis. In this study, we report that trifluoperazine and related phenothiazines block functions associated with Type IV pili in different bacterial pathogens, by affecting piliation within minutes. Using Neisseria meningitidis as a paradigm of Gram-negative bacterial pathogens that require Type IV pili for pathogenesis, we show that piliation is sensitive to altered activity of the Na+ pumping NADH-ubiquinone oxidoreductase (Na+-NQR) complex and that these compounds probably altered the establishment of the sodium gradient. In vivo, these compounds exert a strong protective effect. They reduce meningococcal colonization of the human vessels and prevent subsequent vascular dysfunctions, intravascular coagulation and overwhelming inflammation, the hallmarks of invasive meningococcal infections. Finally, they reduce lethality. This work provides a proof of concept that compounds with activity against bacterial Type IV pili could beneficially participate in the treatment of infections caused by Type IV pilus-expressing bacteria.
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Affiliation(s)
- Kevin Denis
- U1016, Institut Cochin, Inserm, Paris, France.,UMR8104, CNRS, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Marion Le Bris
- U1016, Institut Cochin, Inserm, Paris, France.,UMR8104, CNRS, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Loic Le Guennec
- U1016, Institut Cochin, Inserm, Paris, France.,UMR8104, CNRS, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Jean-Philippe Barnier
- U1151, Institut Necker Enfants Malades, Inserm, Paris, France.,UMR 8253, CNRS, Paris, France.,Faculté de Médecine, Université Paris Descartes, Sorbonne Paris Cité, Paris, France.,Hôpital Necker Enfants Malades, Assistance Publique - Hôpitaux de Paris, Paris, France
| | - Camille Faure
- U1016, Institut Cochin, Inserm, Paris, France.,UMR8104, CNRS, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Anne Gouge
- U1016, Institut Cochin, Inserm, Paris, France.,UMR8104, CNRS, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Haniaa Bouzinba-Ségard
- U1016, Institut Cochin, Inserm, Paris, France.,UMR8104, CNRS, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Anne Jamet
- U1151, Institut Necker Enfants Malades, Inserm, Paris, France.,UMR 8253, CNRS, Paris, France.,Faculté de Médecine, Université Paris Descartes, Sorbonne Paris Cité, Paris, France.,Hôpital Necker Enfants Malades, Assistance Publique - Hôpitaux de Paris, Paris, France
| | - Daniel Euphrasie
- U1151, Institut Necker Enfants Malades, Inserm, Paris, France.,UMR 8253, CNRS, Paris, France.,Faculté de Médecine, Université Paris Descartes, Sorbonne Paris Cité, Paris, France.,Hôpital Necker Enfants Malades, Assistance Publique - Hôpitaux de Paris, Paris, France
| | - Beatrice Durel
- U1016, Institut Cochin, Inserm, Paris, France.,UMR8104, CNRS, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Nicolas Barois
- Cellular Microbiology and Physics of Infection Group, Centre for Infection and Immunity of Lille, Institut Pasteur de Lille, Lille, France.,UMR 8204, CNRS, Lille, France.,U1019, Inserm, Lille, France.,Université de Lille, Lille, France
| | - Philippe Pelissier
- Service de Chirurgie Reconstructrice et Plastique, Fondation Hôpital Saint Joseph, Paris, France
| | - Philippe C Morand
- U1016, Institut Cochin, Inserm, Paris, France.,UMR8104, CNRS, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Mathieu Coureuil
- U1151, Institut Necker Enfants Malades, Inserm, Paris, France.,UMR 8253, CNRS, Paris, France.,Faculté de Médecine, Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Frank Lafont
- Cellular Microbiology and Physics of Infection Group, Centre for Infection and Immunity of Lille, Institut Pasteur de Lille, Lille, France.,UMR 8204, CNRS, Lille, France.,U1019, Inserm, Lille, France.,Université de Lille, Lille, France
| | - Olivier Join-Lambert
- U1151, Institut Necker Enfants Malades, Inserm, Paris, France.,UMR 8253, CNRS, Paris, France.,Faculté de Médecine, Université Paris Descartes, Sorbonne Paris Cité, Paris, France.,Hôpital Necker Enfants Malades, Assistance Publique - Hôpitaux de Paris, Paris, France
| | - Xavier Nassif
- U1151, Institut Necker Enfants Malades, Inserm, Paris, France.,UMR 8253, CNRS, Paris, France.,Faculté de Médecine, Université Paris Descartes, Sorbonne Paris Cité, Paris, France.,Hôpital Necker Enfants Malades, Assistance Publique - Hôpitaux de Paris, Paris, France
| | - Sandrine Bourdoulous
- U1016, Institut Cochin, Inserm, Paris, France. .,UMR8104, CNRS, Paris, France. .,Université Paris Descartes, Sorbonne Paris Cité, Paris, France.
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10
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Genus-Wide Comparative Genomics Analysis of Neisseria to Identify New Genes Associated with Pathogenicity and Niche Adaptation of Neisseria Pathogens. Int J Genomics 2019; 2019:6015730. [PMID: 30775379 PMCID: PMC6350579 DOI: 10.1155/2019/6015730] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Revised: 10/06/2018] [Accepted: 10/09/2018] [Indexed: 12/15/2022] Open
Abstract
N. gonorrhoeae and N. meningitidis, the only two human pathogens of Neisseria, are closely related species. But the niches they survived in and their pathogenic characteristics are distinctly different. However, the genetic basis of these differences has not yet been fully elucidated. In this study, comparative genomics analysis was performed based on 15 N. gonorrhoeae, 75 N. meningitidis, and 7 nonpathogenic Neisseria genomes. Core-pangenome analysis found 1111 conserved gene families among them, and each of these species groups had opening pangenome. We found that 452, 78, and 319 gene families were unique in N. gonorrhoeae, N. meningitidis, and both of them, respectively. Those unique gene families were regarded as candidates that related to their pathogenicity and niche adaptation. The relationships among them have been partly verified by functional annotation analysis. But at least one-third genes for each gene set have not found the certain functional information. Simple sequence repeat (SSR), the basis of gene phase variation, was found abundant in the membrane or related genes of each unique gene set, which may facilitate their adaptation to variable host environments. Protein-protein interaction (PPI) analysis found at least five distinct PPI clusters in N. gonorrhoeae and four in N. meningitides, and 167 and 52 proteins with unknown function were contained within them, respectively.
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11
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Zhang Z, Chen G, Hu J, Hussain W, Fan F, Yang Y, Zhou Z, Fang X, Zhu J, Chen WH, Liu Z. Mr.Vc: a database of microarray and RNA-seq of Vibrio cholerae. DATABASE-THE JOURNAL OF BIOLOGICAL DATABASES AND CURATION 2019; 2019:5522264. [PMID: 31231774 PMCID: PMC6597751 DOI: 10.1093/database/baz069] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 04/16/2019] [Accepted: 05/07/2019] [Indexed: 01/02/2023]
Abstract
Gram-negative bacterium Vibrio cholerae is the causative agent of cholera, a life-threatening diarrheal disease. During its infectious cycle, V. cholerae routinely switches niches between aquatic environment and host gastrointestinal tract, in which V. cholerae modulates its transcriptome pattern accordingly for better survival and proliferation. A comprehensive resource for V. cholerae transcriptome will be helpful for cholera research, including prevention, diagnosis and intervention strategies. In this study, we constructed a microarray and RNA-seq database of V. cholerae (Mr.Vc), containing gene transcriptional expression data of 145 experimental conditions of V. cholerae from various sources, covering 25 937 entries of differentially expressed genes. In addition, we collected relevant information including gene annotation, operons they may belong to and possible interaction partners of their protein products. With Mr.Vc, users can easily find transcriptome data they are interested in, such as the experimental conditions in which a gene of interest was differentially expressed in, or all genes that were differentially expressed in an experimental condition. We believe that Mr.Vc database is a comprehensive data repository dedicated to V. cholerae and could be a useful resource for all researchers in related fields. Mr.Vc is available for free at http://bioinfo.life.hust.edu.cn/mrvc.
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Affiliation(s)
- Zhiyuan Zhang
- Department of Biotechnology, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Guozhong Chen
- Department of Biotechnology, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Jun Hu
- Department of Biotechnology, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Wajid Hussain
- Department of Biotechnology, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Fenxia Fan
- State Key Laboratory of Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China
| | - Yalin Yang
- Sino-Norway Fish Gastrointestinal Microbiota Joint Lab, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Zhigang Zhou
- Sino-Norway Fish Gastrointestinal Microbiota Joint Lab, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Xiaodong Fang
- The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Bioinformatics Group, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou 510120, China
| | - Jun Zhu
- Department of Biotechnology, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Wei-Hua Chen
- Department of Biotechnology, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, China.,College of Life Science, Henan Normal University, Xinxiang 453007, China.,Huazhong University of Science and Technology Ezhou Industrial Technology Research Institute, Ezhou, Hubei 436044, China
| | - Zhi Liu
- Department of Biotechnology, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, China
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12
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Raba DA, Rosas-Lemus M, Menzer WM, Li C, Fang X, Liang P, Tuz K, Minh DDL, Juárez O. Characterization of the Pseudomonas aeruginosa NQR complex, a bacterial proton pump with roles in autopoisoning resistance. J Biol Chem 2018; 293:15664-15677. [PMID: 30135204 DOI: 10.1074/jbc.ra118.003194] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Revised: 08/13/2018] [Indexed: 12/22/2022] Open
Abstract
Pseudomonas aeruginosa is a Gram-negative bacterium responsible for a large number of nosocomial infections. The P. aeruginosa respiratory chain contains the ion-pumping NADH:ubiquinone oxidoreductase (NQR). This enzyme couples the transfer of electrons from NADH to ubiquinone to the pumping of sodium ions across the cell membrane, generating a gradient that drives essential cellular processes in many bacteria. In this study, we characterized P. aeruginosa NQR (Pa-NQR) to elucidate its physiologic function. Our analyses reveal that Pa-NQR, in contrast with NQR homologues from other bacterial species, is not a sodium pump, but rather a completely new form of proton pump. Homology modeling and molecular dynamics simulations suggest that cation selectivity could be determined by the exit ion channels. We also show that Pa-NQR is resistant to the inhibitor 2-n-heptyl-4-hydroxyquinoline N-oxide (HQNO). HQNO is a quinolone secreted by P. aeruginosa during infection that acts as a quorum sensing agent and also has bactericidal properties against other bacteria. Using comparative analysis and computational modeling of the ubiquinone-binding site, we identified the specific residues that confer resistance toward this inhibitor. In summary, our findings indicate that Pa-NQR is a proton pump rather than a sodium pump and is highly resistant against the P. aeruginosa-produced compound HQNO, suggesting an important role in the adaptation against autotoxicity. These results provide a deep understanding of the metabolic role of NQR in P. aeruginosa and provide insight into the structural factors that determine the functional specialization in this family of respiratory complexes.
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Affiliation(s)
| | | | - William M Menzer
- From the Departments of Biological Sciences and.,Chemistry, Illinois Institute of Technology, Chicago, Illinois 60616
| | - Chen Li
- Chemistry, Illinois Institute of Technology, Chicago, Illinois 60616
| | - Xuan Fang
- From the Departments of Biological Sciences and
| | | | - Karina Tuz
- From the Departments of Biological Sciences and
| | - David D L Minh
- Chemistry, Illinois Institute of Technology, Chicago, Illinois 60616
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Metabolic Reprogramming of Vibrio cholerae Impaired in Respiratory NADH Oxidation Is Accompanied by Increased Copper Sensitivity. J Bacteriol 2018; 200:JB.00761-17. [PMID: 29735761 DOI: 10.1128/jb.00761-17] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2017] [Accepted: 05/01/2018] [Indexed: 11/20/2022] Open
Abstract
The electrogenic, sodium ion-translocating NADH:quinone oxidoreductase (NQR) from Vibrio cholerae is frequent in pathogenic bacteria and a potential target for antibiotics. NQR couples the oxidation of NADH to the formation of a sodium motive force (SMF) and therefore drives important processes, such as flagellar rotation, substrate uptake, and energy-dissipating cation-proton antiport. We performed a quantitative proteome analysis of V. cholerae O395N1 compared to its variant lacking the NQR using minimal medium with glucose as the carbon source. We found 84 proteins (regulation factor of ≥2) to be changed in abundance. The loss of NQR resulted in a decrease in the abundance of enzymes of the oxidative branch of the tricarboxylic acid (TCA) cycle and an increase in abundance of virulence factors AcfC and TcpA. Most unexpected, the copper resistance proteins CopA, CopG, and CueR were decreased in the nqr deletion strain. As a consequence, the mutant exhibited diminished resistance to copper compared to the reference strain, as confirmed in growth studies using either glucose or mixed amino acids as carbon sources. We propose that the observed adaptations of the nqr deletion strain represent a coordinated response which counteracts a drop in transmembrane voltage that challenges V. cholerae in its different habitats.IMPORTANCE The importance of the central metabolism for bacterial virulence has raised interest in studying catabolic enzymes not present in the host, such as NQR, as putative targets for antibiotics. Vibrio cholerae lacking the NQR, which is studied here, is a model to estimate the impact of specific NQR inhibitors on the phenotype of a pathogen. Our comparative proteomic study provides a framework to evaluate the chances of success of compounds directed against NQR with respect to their bacteriostatic or bactericidal action.
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14
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Abstract
Metabolomics is an "omics" approach to quantitatively measure a large set of metabolites. In this chapter, we describe an example method for performing liquid chromatography coupled to mass spectrometry (LC-MS)-based untargeted metabolomics on a cell extract from Vibrio cholerae.
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Affiliation(s)
- Yusuke Minato
- Department of Microbiology and Immunology, University of Minnesota Medical School, Minneapolis, MN, USA
| | - Jay S Kirkwood
- Department of Pharmaceutics, University of Washington, Seattle, WA, USA
| | - Claudia C Häse
- Department of Biomedical Sciences, College of Veterinary Medicine, Oregon State University, Corvallis, OR, USA.
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15
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Vorburger T, Nedielkov R, Brosig A, Bok E, Schunke E, Steffen W, Mayer S, Götz F, Möller HM, Steuber J. Role of the Na(+)-translocating NADH:quinone oxidoreductase in voltage generation and Na(+) extrusion in Vibrio cholerae. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2015; 1857:473-82. [PMID: 26721205 DOI: 10.1016/j.bbabio.2015.12.010] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Revised: 11/25/2015] [Accepted: 12/16/2015] [Indexed: 01/05/2023]
Abstract
For Vibrio cholerae, the coordinated import and export of Na(+) is crucial for adaptation to habitats with different osmolarities. We investigated the Na(+)-extruding branch of the sodium cycle in this human pathogen by in vivo (23)Na-NMR spectroscopy. The Na(+) extrusion activity of cells was monitored after adding glucose which stimulated respiration via the Na(+)-translocating NADH:quinone oxidoreductase (Na(+)-NQR). In a V. cholerae deletion mutant devoid of the Na(+)-NQR encoding genes (nqrA-F), rates of respiratory Na(+) extrusion were decreased by a factor of four, but the cytoplasmic Na(+) concentration was essentially unchanged. Furthermore, the mutant was impaired in formation of transmembrane voltage (ΔΨ, inside negative) and did not grow under hypoosmotic conditions at pH8.2 or above. This growth defect could be complemented by transformation with the plasmid encoded nqr operon. In an alkaline environment, Na(+)/H(+) antiporters acidify the cytoplasm at the expense of the transmembrane voltage. It is proposed that, at alkaline pH and limiting Na(+) concentrations, the Na(+)-NQR is crucial for generation of a transmembrane voltage to drive the import of H(+) by electrogenic Na(+)/H(+) antiporters. Our study provides the basis to understand the role of the Na(+)-NQR in pathogenicity of V. cholerae and other pathogens relying on this primary Na(+) pump for respiration.
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Affiliation(s)
- Thomas Vorburger
- Institute of Microbiology, University of Hohenheim (Stuttgart), Garbenstraße 30, 70599 Stuttgart, Germany
| | - Ruslan Nedielkov
- Department of Chemistry, University of Konstanz, Universitätsstraße 10, 78457 Konstanz, Germany
| | - Alexander Brosig
- Department of Biology, University of Konstanz, Universitätsstraße 10, 78457 Konstanz, Germany
| | - Eva Bok
- Institute of Microbiology, University of Hohenheim (Stuttgart), Garbenstraße 30, 70599 Stuttgart, Germany
| | - Emina Schunke
- Institute of Microbiology, University of Hohenheim (Stuttgart), Garbenstraße 30, 70599 Stuttgart, Germany
| | - Wojtek Steffen
- Institute of Microbiology, University of Hohenheim (Stuttgart), Garbenstraße 30, 70599 Stuttgart, Germany
| | - Sonja Mayer
- Interfaculty Institute of Microbiology and Infection Medicine, Department of Microbial Genetics, University of Tübingen, Auf der Morgenstelle 28, 72076 Tübingen, Germany
| | - Friedrich Götz
- Interfaculty Institute of Microbiology and Infection Medicine, Department of Microbial Genetics, University of Tübingen, Auf der Morgenstelle 28, 72076 Tübingen, Germany
| | - Heiko M Möller
- Department of Chemistry, University of Konstanz, Universitätsstraße 10, 78457 Konstanz, Germany.
| | - Julia Steuber
- Institute of Microbiology, University of Hohenheim (Stuttgart), Garbenstraße 30, 70599 Stuttgart, Germany.
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16
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Christen M, Beusch C, Bösch Y, Cerletti D, Flores-Tinoco CE, Del Medico L, Tschan F, Christen B. Quantitative Selection Analysis of Bacteriophage φCbK Susceptibility in Caulobacter crescentus. J Mol Biol 2015; 428:419-30. [PMID: 26593064 DOI: 10.1016/j.jmb.2015.11.018] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2015] [Revised: 11/16/2015] [Accepted: 11/17/2015] [Indexed: 11/25/2022]
Abstract
Classical molecular genetics uses stringent selective conditions to identify mutants with distinct phenotypic responses. Mutations giving rise to less pronounced phenotypes are often missed. However, to gain systems-level insights into complex genetic interaction networks requires genome-wide assignment of quantitative phenotypic traits. In this paper, we present a quantitative selection approach coupled with transposon sequencing (QS-TnSeq) to globally identify the cellular components that orchestrate susceptibility of the cell cycle model bacterium Caulobacter crescentus toward bacteriophage φCbK infection. We found that 135 genes representing 3.30% of the Caulobacter genome exhibit significant accumulation of transposon insertions upon φCbK selection. More than 85% thereof consist of new factors not previously associated with phage φCbK susceptibility. Using hierarchical clustering of dose-dependent TnSeq datasets, we grouped these genes into functional modules that correlate with different stages of the φCbK infection process. We assign φCbK susceptibility to eight new genes that represent novel components of the pilus secretion machinery. Further, we demonstrate that, from 86 motility genes, only seven genes encoding structural and regulatory components of the flagellar hook increase phage resistance when disrupted by transposons, suggesting a link between flagellar hook assembly and pili biogenesis. In addition, we observe high recovery of Tn5 insertions within regulatory sequences of the genes encoding the essential NADH:ubiquinone oxidoreductase complex indicating that intact proton motive force is crucial for effective phage propagation. In sum, QS-TnSeq is broadly applicable to perform quantitative and genome-wide systems-genetics analysis of complex phenotypic traits.
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Affiliation(s)
- Matthias Christen
- Institute of Molecular Systems Biology, Eidgenössische Technische Hochschule (ETH) Zürich, CH-8093 Zürich, Switzerland
| | - Christian Beusch
- Institute of Molecular Systems Biology, Eidgenössische Technische Hochschule (ETH) Zürich, CH-8093 Zürich, Switzerland
| | - Yvonne Bösch
- Institute of Molecular Systems Biology, Eidgenössische Technische Hochschule (ETH) Zürich, CH-8093 Zürich, Switzerland
| | - Dario Cerletti
- Institute of Molecular Systems Biology, Eidgenössische Technische Hochschule (ETH) Zürich, CH-8093 Zürich, Switzerland
| | - Carlos Eduardo Flores-Tinoco
- Institute of Molecular Systems Biology, Eidgenössische Technische Hochschule (ETH) Zürich, CH-8093 Zürich, Switzerland; Life Science Zürich PhD Program on Systems Biology, Zürich, Switzerland
| | - Luca Del Medico
- Institute of Molecular Systems Biology, Eidgenössische Technische Hochschule (ETH) Zürich, CH-8093 Zürich, Switzerland
| | - Flavia Tschan
- Institute of Molecular Systems Biology, Eidgenössische Technische Hochschule (ETH) Zürich, CH-8093 Zürich, Switzerland
| | - Beat Christen
- Institute of Molecular Systems Biology, Eidgenössische Technische Hochschule (ETH) Zürich, CH-8093 Zürich, Switzerland.
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Halang P, Vorburger T, Steuber J. Serine 26 in the PomB subunit of the flagellar motor is essential for hypermotility of Vibrio cholerae. PLoS One 2015; 10:e0123518. [PMID: 25874792 PMCID: PMC4398553 DOI: 10.1371/journal.pone.0123518] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2014] [Accepted: 02/19/2015] [Indexed: 11/18/2022] Open
Abstract
Vibrio cholerae is motile by means of its single polar flagellum which is driven by the sodium-motive force. In the motor driving rotation of the flagellar filament, a stator complex consisting of subunits PomA and PomB converts the electrochemical sodium ion gradient into torque. Charged or polar residues within the membrane part of PomB could act as ligands for Na+, or stabilize a hydrogen bond network by interacting with water within the putative channel between PomA and PomB. By analyzing a large data set of individual tracks of swimming cells, we show that S26 located within the transmembrane helix of PomB is required to promote very fast swimming of V. cholerae. Loss of hypermotility was observed with the S26T variant of PomB at pH 7.0, but fast swimming was restored by decreasing the H+ concentration of the external medium. Our study identifies S26 as a second important residue besides D23 in the PomB channel. It is proposed that S26, together with D23 located in close proximity, is important to perturb the hydration shell of Na+ before its passage through a constriction within the stator channel.
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Affiliation(s)
- Petra Halang
- Institute of Microbiology, University of Hohenheim (Stuttgart), Stuttgart, Germany
| | - Thomas Vorburger
- Institute of Microbiology, University of Hohenheim (Stuttgart), Stuttgart, Germany
- * E-mail: (TV); (JS)
| | - Julia Steuber
- Institute of Microbiology, University of Hohenheim (Stuttgart), Stuttgart, Germany
- * E-mail: (TV); (JS)
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