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Archambaud C, Nunez N, da Silva RAG, Kline KA, Serror P. Enterococcus faecalis: an overlooked cell invader. Microbiol Mol Biol Rev 2024:e0006924. [PMID: 39239986 DOI: 10.1128/mmbr.00069-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/07/2024] Open
Abstract
SUMMARYEnterococcus faecalis and Enterococcus faecium are human pathobionts that exhibit a dual lifestyle as commensal and pathogenic bacteria. The pathogenic lifestyle is associated with specific conditions involving host susceptibility and intestinal overgrowth or the use of a medical device. Although the virulence of E. faecium appears to benefit from its antimicrobial resistance, E. faecalis is recognized for its higher pathogenic potential. E. faecalis has long been considered a predominantly extracellular pathogen; it adheres to and is taken up by a wide range of mammalian cells, albeit with less efficiency than classical intracellular enteropathogens. Carbohydrate structures, rather than proteinaceous moieties, are likely to be primarily involved in the adhesion of E. faecalis to epithelial cells. Consistently, few adhesins have been implicated in the adhesion of E. faecalis to epithelial cells. On the host side, very little is known about cognate receptors, except for the role of glycosaminoglycans during macrophage infection. Several lines of evidence indicate that E. faecalis internalization may involve a zipper-like mechanism as well as a macropinocytosis pathway. Conversely, E. faecalis can use several strategies to prevent engulfment in phagocytes. However, the bacterial and host mechanisms underlying cell infection by E. faecalis are still in their infancy. The most recent striking finding is the existence of an intracellular lifestyle where E. faecalis can replicate within a variety of host cells. In this review, we summarize and discuss the current knowledge of E. faecalis-host cell interactions and argue on the need for further mechanistic studies to prevent or reduce infections.
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Affiliation(s)
- Cristel Archambaud
- Université Paris-Saclay, INRAE, AgroParisTech, Micalis Institute, Jouy-en-Josas, France
| | - Natalia Nunez
- Université Paris-Saclay, INRAE, AgroParisTech, Micalis Institute, Jouy-en-Josas, France
| | - Ronni A G da Silva
- Singapore-MIT Alliance for Research and Technology, Antimicrobial Drug Resistance Interdisciplinary Research Group, Singapore, Singapore
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore
| | - Kimberly A Kline
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore
- Department of Microbiology and Molecular Medicine, University of Geneva, Geneva, Switzerland
| | - Pascale Serror
- Université Paris-Saclay, INRAE, AgroParisTech, Micalis Institute, Jouy-en-Josas, France
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2
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Mallawaarachchi S, Tonkin-Hill G, Pöntinen A, Calland J, Gladstone R, Arredondo-Alonso S, MacAlasdair N, Thorpe H, Top J, Sheppard S, Balding D, Croucher N, Corander J. Detecting co-selection through excess linkage disequilibrium in bacterial genomes. NAR Genom Bioinform 2024; 6:lqae061. [PMID: 38846349 PMCID: PMC11155488 DOI: 10.1093/nargab/lqae061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2024] [Revised: 04/15/2024] [Accepted: 05/14/2024] [Indexed: 06/09/2024] Open
Abstract
Population genomics has revolutionized our ability to study bacterial evolution by enabling data-driven discovery of the genetic architecture of trait variation. Genome-wide association studies (GWAS) have more recently become accompanied by genome-wide epistasis and co-selection (GWES) analysis, which offers a phenotype-free approach to generating hypotheses about selective processes that simultaneously impact multiple loci across the genome. However, existing GWES methods only consider associations between distant pairs of loci within the genome due to the strong impact of linkage-disequilibrium (LD) over short distances. Based on the general functional organisation of genomes it is nevertheless expected that majority of co-selection and epistasis will act within relatively short genomic proximity, on co-variation occurring within genes and their promoter regions, and within operons. Here, we introduce LDWeaver, which enables an exhaustive GWES across both short- and long-range LD, to disentangle likely neutral co-variation from selection. We demonstrate the ability of LDWeaver to efficiently generate hypotheses about co-selection using large genomic surveys of multiple major human bacterial pathogen species and validate several findings using functional annotation and phenotypic measurements. Our approach will facilitate the study of bacterial evolution in the light of rapidly expanding population genomic data.
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Affiliation(s)
| | | | - Anna K Pöntinen
- Department of Biostatistics, University of Oslo, Oslo, Norway
- Norwegian National Advisory Unit on Detection of Antimicrobial Resistance, Department of Microbiology and Infection Control, University Hospital of North Norway, Tromsø, Norway
| | - Jessica K Calland
- Oslo Centre for Biostatistics and Epidemiology, Oslo University Hospital, Oslo, Norway
| | | | | | | | - Harry A Thorpe
- Department of Biostatistics, University of Oslo, Oslo, Norway
| | - Janetta Top
- Department of Medical Microbiology, UMC Utrecht, Utrecht, The Netherlands
| | - Samuel K Sheppard
- Ineos Oxford Institute of Antimicrobial Research, Department of Biology, University of Oxford, Oxford, United Kingdom
| | - David Balding
- Melbourne Integrative Genomics, School of BioSciences and School of Mathematics & Statistics, University of Melbourne, Parkville, Victoria, Australia
| | - Nicholas J Croucher
- Department of Infectious Disease Epidemiology, School of Public Health, Imperial College London, United Kingdom
- MRC Centre for Global Infectious Disease Analysis, School of Public Health, Imperial College London, United Kingdom
| | - Jukka Corander
- Department of Biostatistics, University of Oslo, Oslo, Norway
- Parasites and Microbes, Wellcome Sanger Institute, Cambridge, UK
- Helsinki Institute of Information Technology, Department of Mathematics and Statistics, University of Helsinki, Helsinki, Finland
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3
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Lê-Bury P, Echenique-Rivera H, Pizarro-Cerdá J, Dussurget O. Determinants of bacterial survival and proliferation in blood. FEMS Microbiol Rev 2024; 48:fuae013. [PMID: 38734892 PMCID: PMC11163986 DOI: 10.1093/femsre/fuae013] [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: 11/06/2023] [Revised: 04/29/2024] [Accepted: 05/10/2024] [Indexed: 05/13/2024] Open
Abstract
Bloodstream infection is a major public health concern associated with high mortality and high healthcare costs worldwide. Bacteremia can trigger fatal sepsis whose prevention, diagnosis, and management have been recognized as a global health priority by the World Health Organization. Additionally, infection control is increasingly threatened by antimicrobial resistance, which is the focus of global action plans in the framework of a One Health response. In-depth knowledge of the infection process is needed to develop efficient preventive and therapeutic measures. The pathogenesis of bloodstream infection is a dynamic process resulting from the invasion of the vascular system by bacteria, which finely regulate their metabolic pathways and virulence factors to overcome the blood immune defenses and proliferate. In this review, we highlight our current understanding of determinants of bacterial survival and proliferation in the bloodstream and discuss their interactions with the molecular and cellular components of blood.
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Affiliation(s)
- Pierre Lê-Bury
- Institut Pasteur, Université Paris Cité, CNRS UMR6047, Yersinia Research Unit, 28 rue du Dr Roux, 75015 Paris, France
- Université Paris-Saclay, Inserm, CEA, Center for Immunology of Viral, Autoimmune, Hematological and Bacterial Diseases (IMVA-HB/IDMIT), 18 route du Panorama, 92260 Fontenay-aux-Roses, France
| | - Hebert Echenique-Rivera
- Institut Pasteur, Université Paris Cité, CNRS UMR6047, Yersinia Research Unit, 28 rue du Dr Roux, 75015 Paris, France
| | - Javier Pizarro-Cerdá
- Institut Pasteur, Université Paris Cité, CNRS UMR6047, Yersinia Research Unit, 28 rue du Dr Roux, 75015 Paris, France
- Institut Pasteur, Université Paris Cité, Yersinia National Reference Laboratory, WHO Collaborating Research & Reference Centre for Plague FRA-146, 28 rue du Dr Roux, 75015 Paris, France
| | - Olivier Dussurget
- Institut Pasteur, Université Paris Cité, CNRS UMR6047, Yersinia Research Unit, 28 rue du Dr Roux, 75015 Paris, France
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4
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Hassan MU, Chaudhuri RR, Williamson MP. DUF916 and DUF3324 in the WxL protein cluster bind to WxL and link bacterial and host surfaces. Protein Sci 2023; 32:e4806. [PMID: 37833244 PMCID: PMC10599100 DOI: 10.1002/pro.4806] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 10/10/2023] [Accepted: 10/11/2023] [Indexed: 10/15/2023]
Abstract
Bacterial WxL proteins contain peptidoglycan-binding WxL domains, which have a dual Trp-x-Leu motif and are involved in virulence. It was recently shown that WxL proteins occur in gene clusters, containing typically a small WxL protein (which in the mature protein consists only of a WxL domain), a large WxL protein (which contains a C-terminal WxL domain with N-terminal host-binding domains), and a conserved protein annotated as a Domain of Unknown Function (DUF). Here we analyze this DUF and show that it contains two tandem domains-DUF916 and DUF3324-which both have an IgG-like fold and together form a single functional unit, connected to a C-terminal transmembrane helix. DUF3324 is a stable domain, while DUF916 is less stable and is likely to require a stabilizing interaction with WxL. The protein is suggested to have an important role to bind and stabilize WxL on the peptidoglycan surface, via the DUF916 domain, and to bind to host cells via the DUF3324 domain. AlphaFold2 predicts that a β-hairpin strand from DUF916 inserts into WxL adjacent to its N-terminus. We therefore propose to rename the DUF916-DUF3324 pair as WxL Interacting Protein (WxLIP), with DUF916, DUF3324 and the transmembrane helix forming the first, second and third domains of WxLIP, which we characterize as peptidoglycan binding domain (PGBD), host binding domain (HBD), and transmembrane helix (TMH) respectively.
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Affiliation(s)
- Mahreen U. Hassan
- School of BiosciencesUniversity of SheffieldSheffieldUK
- Present address:
Department of MicrobiologyShaheed Benazir Bhutto Women UniversityPeshawarPakistan
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Nunez N, Derré-Bobillot A, Trainel N, Lakisic G, Lecomte A, Mercier-Nomé F, Cassard AM, Bierne H, Serror P, Archambaud C. The unforeseen intracellular lifestyle of Enterococcus faecalis in hepatocytes. Gut Microbes 2022; 14:2058851. [PMID: 35373699 PMCID: PMC8986240 DOI: 10.1080/19490976.2022.2058851] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Accepted: 03/15/2022] [Indexed: 02/04/2023] Open
Abstract
Enterococcus faecalis is a bacterial species present at a subdominant level in the human gut microbiota. This commensal turns into an opportunistic pathogen under specific conditions involving dysbiosis and host immune deficiency. E. faecalis is one of the rare pathobionts identified to date as contributing to liver damage in alcoholic liver disease. We have previously observed that E. faecalis is internalized in hepatocytes. Here, the survival and fate of E. faecalis was examined in hepatocytes, the main epithelial cell type in the liver. Although referred to as an extracellular pathogen, we demonstrate that E. faecalis is able to survive and divide in hepatocytes, and form intracellular clusters in two distinct hepatocyte cell lines, in primary mouse hepatocytes, as well as in vivo. This novel process extends to kidney cells. Unraveling the intracellular lifestyle of E. faecalis, our findings contribute to the understanding of pathobiont-driven diseases.
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Affiliation(s)
- Natalia Nunez
- Université -Saclay, Inrae, AgroParisTech, Micalis Institute, Jouy-en-Josas, France
| | | | - Nicolas Trainel
- Université Paris-Saclay, Inserm U996, Inflammation, Microbiome and Immunosurveillance, Clamart, France
| | - Goran Lakisic
- Université -Saclay, Inrae, AgroParisTech, Micalis Institute, Jouy-en-Josas, France
| | - Alexandre Lecomte
- Université -Saclay, Inrae, AgroParisTech, Micalis Institute, Jouy-en-Josas, France
| | - Françoise Mercier-Nomé
- Université Paris-Saclay, INSERM, CNRS, Institut Paris Saclay d’Innovation Thérapeutique, Châtenay-Malabry, France
| | - Anne-Marie Cassard
- Université Paris-Saclay, Inserm U996, Inflammation, Microbiome and Immunosurveillance, Clamart, France
| | - Hélène Bierne
- Université -Saclay, Inrae, AgroParisTech, Micalis Institute, Jouy-en-Josas, France
| | - Pascale Serror
- Université -Saclay, Inrae, AgroParisTech, Micalis Institute, Jouy-en-Josas, France
| | - Cristel Archambaud
- Université -Saclay, Inrae, AgroParisTech, Micalis Institute, Jouy-en-Josas, France
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Involvement of Chromosomally Encoded Homologs of the RRNPP Protein Family in Enterococcus faecalis Biofilm Formation and Urinary Tract Infection Pathogenesis. J Bacteriol 2020; 202:JB.00063-20. [PMID: 32540933 DOI: 10.1128/jb.00063-20] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Accepted: 06/02/2020] [Indexed: 11/20/2022] Open
Abstract
Enterococcus faecalis is an opportunistic pathogen capable of causing infections, including endocarditis and urinary tract infections (UTI). One of the well-characterized quorum-sensing pathways in E. faecalis involves coordination of the conjugal transfer of pheromone-responsive plasmids by PrgX, a member of the RRNPP protein family. Members of this protein family in various Firmicutes have also been shown to contribute to numerous cellular processes, including sporulation, competence, conjugation, nutrient sensing, biofilm formation, and virulence. As PrgX is a plasmid-encoded RRNPP family member, we surveyed the genome of the multidrug-resistant strain V583 for additional RRNPP homologs using computational searches and refined those identified hits for predicted structural similarities to known RRNPP family members. This led us to investigate the contribution of the chromosomally encoded RRNPP homologs to biofilm processes and pathogenesis in a catheter-associated urinary tract infection (CAUTI) model. In this study, we identified five such homologs and report that 3 of the 5 homologs, EF0073, EF1599, and EF1316, affect biofilm formation as well as outcomes in the CAUTI model.IMPORTANCE Enterococcus faecalis causes health care-associated infections and displays resistance to a variety of broad-spectrum antibiotics by acquisition of resistance traits as well as the ability to form biofilms. Even though a growing number of factors related to biofilm formation have been identified, mechanisms that contribute to biofilm formation are still largely unknown. Members of the RRNPP protein family regulate a diverse set of biological reactions in low-G+C Gram-positive bacteria (Firmicutes). Here, we identify three predicted structural homologs of the RRNPP family, EF0073, EF1599, and EF1316, which affect biofilm formation and CAUTI pathogenesis.
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Dr. Jekyll and Mr. Hide: How Enterococcus faecalis Subverts the Host Immune Response to Cause Infection. J Mol Biol 2019; 431:2932-2945. [DOI: 10.1016/j.jmb.2019.05.030] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2019] [Revised: 05/15/2019] [Accepted: 05/20/2019] [Indexed: 02/06/2023]
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Ponce JB, Midena RZ, Pinke KH, Weckwerth PH, Andrade FBD, Lara VS. In vitro treatment of Enterococcus faecalis with calcium hydroxide impairs phagocytosis by human macrophages. Acta Odontol Scand 2019; 77:158-163. [PMID: 30618320 DOI: 10.1080/00016357.2018.1533142] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
OBJECTIVE Monocyte-derived macrophages (MDMs) ability to phagocytize and produce nitric oxide (NO) was tested against root-canal strains of Enterococcus faecalis submitted to alkaline stress. Root-canal strains were also compared with urine Enterococci. MATERIALS AND METHODS Enterococcus faecalis were stressed with alkaline-BHI broth and incubated in vitro at a cell/bacteria ratio of 1:5. Phagocytosis was analyzed by fluorescence microscopy using acridine orange stain, and NO concentration was measured in supernatants. RESULTS AND CONCLUSIONS Alkaline-stress significantly impaired MDMs phagocytosis of E. faecalis strains analyzed, except in ATCC4083 isolated from a pulpless tooth, but NO production was unchanged. Comparison of different strains showed the urine isolate had higher NO levels than root canal strains. Alterations in the bacterial cell wall structures after alkaline-stress possibly made bacteria less recognizable and phagocytized by MDMs but did not affect their ability to activate NO production. Furthermore, root canal strains elicited different responses by immune cells compared with strains from urine. Clinically, impaired phagocytosis of E. faecalis could contribute to their persistence in root canal systems previously treated with calcium hydroxide.
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Affiliation(s)
- José Burgos Ponce
- Department of Surgery, Stomatology, Pathology and Radiology, Bauru School of Dentistry, University of São Paulo, Bauru, Brazil
| | - Raquel Zanin Midena
- Department of Operative Dentistry, Endodontics and Dental Materials, Bauru School of Dentistry, University of São Paulo, Bauru, Brazil
| | - Karen Henriette Pinke
- Department of Surgery, Stomatology, Pathology and Radiology, Bauru School of Dentistry, University of São Paulo, Bauru, Brazil
| | | | - Flaviana Bombarda de Andrade
- Department of Operative Dentistry, Endodontics and Dental Materials, Bauru School of Dentistry, University of São Paulo, Bauru, Brazil
| | - Vanessa Soares Lara
- Department of Surgery, Stomatology, Pathology and Radiology, Bauru School of Dentistry, University of São Paulo, Bauru, Brazil
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Desvaux M, Candela T, Serror P. Surfaceome and Proteosurfaceome in Parietal Monoderm Bacteria: Focus on Protein Cell-Surface Display. Front Microbiol 2018; 9:100. [PMID: 29491848 PMCID: PMC5817068 DOI: 10.3389/fmicb.2018.00100] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Accepted: 01/16/2018] [Indexed: 12/12/2022] Open
Abstract
The cell envelope of parietal monoderm bacteria (archetypal Gram-positive bacteria) is formed of a cytoplasmic membrane (CM) and a cell wall (CW). While the CM is composed of phospholipids, the CW is composed at least of peptidoglycan (PG) covalently linked to other biopolymers, such as teichoic acids, polysaccharides, and/or polyglutamate. Considering the CW is a porous structure with low selective permeability contrary to the CM, the bacterial cell surface hugs the molecular figure of the CW components as a well of the external side of the CM. While the surfaceome corresponds to the totality of the molecules found at the bacterial cell surface, the proteinaceous complement of the surfaceome is the proteosurfaceome. Once translocated across the CM, secreted proteins can either be released in the extracellular milieu or exposed at the cell surface by associating to the CM or the CW. Following the gene ontology (GO) for cellular components, cell-surface proteins at the CM can either be integral (GO: 0031226), i.e., the integral membrane proteins, or anchored to the membrane (GO: 0046658), i.e., the lipoproteins. At the CW (GO: 0009275), cell-surface proteins can be covalently bound, i.e., the LPXTG-proteins, or bound through weak interactions to the PG or wall polysaccharides, i.e., the cell wall binding proteins. Besides monopolypeptides, some proteins can associate to each other to form supramolecular protein structures of high molecular weight, namely the S-layer, pili, flagella, and cellulosomes. After reviewing the cell envelope components and the different molecular mechanisms involved in protein attachment to the cell envelope, perspectives in investigating the proteosurfaceome in parietal monoderm bacteria are further discussed.
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Affiliation(s)
- Mickaël Desvaux
- Université Clermont Auvergne, INRA, UMR454 MEDiS, Clermont-Ferrand, France
| | - Thomas Candela
- EA4043 Unité Bactéries Pathogènes et Santé, Châtenay-Malabry, France
| | - Pascale Serror
- Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
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Exploration of the role of the virulence factor ElrA during Enterococcus faecalis cell infection. Sci Rep 2018; 8:1749. [PMID: 29379180 PMCID: PMC5788860 DOI: 10.1038/s41598-018-20206-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Accepted: 01/15/2018] [Indexed: 12/15/2022] Open
Abstract
Enterococcus faecalis, an organism generally not pathogenic for healthy humans, has the potential to cause disease in susceptible hosts. While it seems to be equipped to interact with and circumvent host immune defense, most of the molecular and cellular mechanisms underlying the enterococcal infectious process remain elusive. Here, we investigated the role of the Enterococcal Leucine Rich protein A (ElrA), an internalin-like protein of E. faecalis also known as a virulence factor. ElrA was previously shown to prevent adhesion to macrophages. We show that ElrA does not inhibit the basic phagocytic process, but is able to prevent sensing and migration of macrophages toward E. faecalis. Presence or absence of FHL2, a eukaryotic partner of ElrA, does not affect the ElrA-dependent mechanism preventing macrophage migration. However, we highlight a partial contribution of FHL2 in ElrA-mediated virulence in vivo. Our results indicate that ElrA plays at least a dual role of which anti-phagocytic activity may contribute to dissemination of extracellular E. faecalis during infection.
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Goh HMS, Yong MHA, Chong KKL, Kline KA. Model systems for the study of Enterococcal colonization and infection. Virulence 2017; 8:1525-1562. [PMID: 28102784 PMCID: PMC5810481 DOI: 10.1080/21505594.2017.1279766] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Revised: 12/30/2016] [Accepted: 01/04/2017] [Indexed: 02/07/2023] Open
Abstract
Enterococcus faecalis and Enterococcus faecium are common inhabitants of the human gastrointestinal tract, as well as frequent opportunistic pathogens. Enterococci cause a range of infections including, most frequently, infections of the urinary tract, catheterized urinary tract, bloodstream, wounds and surgical sites, and heart valves in endocarditis. Enterococcal infections are often biofilm-associated, polymicrobial in nature, and resistant to antibiotics of last resort. Understanding Enterococcal mechanisms of colonization and pathogenesis are important for identifying new ways to manage and intervene with these infections. We review vertebrate and invertebrate model systems applied to study the most common E. faecalis and E. faecium infections, with emphasis on recent findings examining Enterococcal-host interactions using these models. We discuss strengths and shortcomings of each model, propose future animal models not yet applied to study mono- and polymicrobial infections involving E. faecalis and E. faecium, and comment on the significance of anti-virulence strategies derived from a fundamental understanding of host-pathogen interactions in model systems.
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Affiliation(s)
- H. M. Sharon Goh
- Singapore Centre for Environmental Life Sciences Engineering, School of Biological Sciences, Nanyang Technological University, Singapore
| | - M. H. Adeline Yong
- Singapore Centre for Environmental Life Sciences Engineering, School of Biological Sciences, Nanyang Technological University, Singapore
| | - Kelvin Kian Long Chong
- Singapore Centre for Environmental Life Sciences Engineering, School of Biological Sciences, Nanyang Technological University, Singapore
- Singapore Centre for Environmental Life Sciences Engineering, Interdisciplinary Graduate School, Nanyang Technological University, Singapore
| | - Kimberly A. Kline
- Singapore Centre for Environmental Life Sciences Engineering, School of Biological Sciences, Nanyang Technological University, Singapore
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The Enterococcus faecalis virulence factor ElrA interacts with the human Four-and-a-Half LIM Domains Protein 2. Sci Rep 2017; 7:4581. [PMID: 28676674 PMCID: PMC5496941 DOI: 10.1038/s41598-017-04875-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Accepted: 05/22/2017] [Indexed: 12/22/2022] Open
Abstract
The commensal bacterium Enterococcus faecalis is a common cause of nosocomial infections worldwide. The increasing prevalence of multi-antibiotic resistant E. faecalis strains reinforces this public health concern. Despite numerous studies highlighting several pathology-related genetic traits, the molecular mechanisms of E. faecalis virulence remain poorly understood. In this work, we studied 23 bacterial proteins that could be considered as virulence factors or involved in the Enterococcus interaction with the host. We systematically tested their interactions with human proteins using the Human ORFeome library, a set of 12,212 human ORFs, in yeast. Among the thousands of tested interactions, one involving the E. faecalis virulence factor ElrA and the human protein FHL2 was evidenced by yeast two-hybrid and biochemically confirmed. Further molecular characterizations allowed defining an FHL2-interacting domain (FID) of ElrA. Deletion of the FID led to an attenuated in vivo phenotype of the mutated strain clearly indicating that this interaction is likely to contribute to the multifactorial virulence of this opportunistic pathogen. Altogether, our results show that FHL2 is the first host cellular protein directly targeted by an E. faecalis virulence factor and that this interaction is involved in Enterococcus pathogenicity.
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