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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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2
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Aono R, Emi S, Okabe-Watanabe K, Nariya H, Matsunaga N, Hitsumoto Y, Katayama S. Autolysin as a fibronectin receptor on the cell surface of Clostridium perfringens. Anaerobe 2023; 83:102769. [PMID: 37544355 DOI: 10.1016/j.anaerobe.2023.102769] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Revised: 06/30/2023] [Accepted: 07/24/2023] [Indexed: 08/08/2023]
Abstract
OBJECTIVE Clostridium perfringens causes food poisoning and gas gangrene, a serious wound-associated infection. C. perfringens cells adhere to collagen via fibronectin (Fn). We investigated whether the peptidoglycan hydrolase of C. perfringens, i.e., autolysin (Acp), is implicated in Fn binding to C. perfringens cells. METHODS This study used recombinant Acp fragments, human Fn and knockout mutants (C. perfringens 13 acp::erm and HN13 ΔfbpC ΔfbpD). Ligand blotting, Western blotting analysis, and complementation tests were performed. The Fn-binding activity of each mutant was evaluated by ELISA. RESULTS From an Fn-binding assay using recombinant Acp fragments, Fn was found to bind to the catalytic domain of Acp. In mutant cells lacking Acp, Fn binding was significantly decreased, but was restored by the complementation of the acp gene. There are three known kinds of Fn-binding proteins in C. perfringens: FbpC, FbpD, and glyceraldehyde-3-phosphate dehydrogenase. We found no difference in Fn-binding activity between the mutant cells lacking both FbpC and FbpD (SAK3 cells) and the wild-type cells, indicating that these Fn-binding proteins are not involved in Fn binding to C. perfringens cells. CONCLUSIONS We found that the Acp is an Fn-binding protein that acts as an Fn receptor on the surface of C. perfringens cells.
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Affiliation(s)
- Riyo Aono
- Department of Material Science, School of Science, Faculty of Science, Okayama University of Science, 1-1 Ridai-cho, Kita-ku, Okayama-shi, Okayama, 700-0005, Japan
| | - Shogo Emi
- Department of Life Science, Faculty of Science, Okayama University of Science, 1-1 Ridai-cho, Kita-ku, Okayama-shi, Okayama, 700-0005, Japan
| | - Kanako Okabe-Watanabe
- Department of Medical Technology, Faculty of Health Science and Technology, Kawasaki University of Medical Welfare, 288 Matsushima, Kurashiki-shi, Okayama, 701-0193, Japan
| | - Hirofumi Nariya
- Laboratory of Food Microbiology, Graduate School of Human Life Science, Jumonji University, 2-1-28 Sugasawa, Niiza-shi, Saitama, 352-8510, Japan
| | - Nozomu Matsunaga
- Department of Life Science, Faculty of Science, Okayama University of Science, 1-1 Ridai-cho, Kita-ku, Okayama-shi, Okayama, 700-0005, Japan
| | - Yasuo Hitsumoto
- Department of Life Science, Faculty of Science, Okayama University of Science, 1-1 Ridai-cho, Kita-ku, Okayama-shi, Okayama, 700-0005, Japan
| | - Seiichi Katayama
- Department of Life Science, Faculty of Science, Okayama University of Science, 1-1 Ridai-cho, Kita-ku, Okayama-shi, Okayama, 700-0005, Japan.
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Neculae E, Gosav EM, Valasciuc E, Dima N, Floria M, Tanase DM. The Oral Microbiota in Valvular Heart Disease: Current Knowledge and Future Directions. LIFE (BASEL, SWITZERLAND) 2023; 13:life13010182. [PMID: 36676130 PMCID: PMC9862471 DOI: 10.3390/life13010182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 12/31/2022] [Accepted: 01/06/2023] [Indexed: 01/11/2023]
Abstract
Oral microbiota formation begins from birth, and everything from genetic components to the environment, alongside the host's behavior (such as diet, smoking, oral hygiene, and even physical activity), contributes to oral microbiota structure. Even though recent studies have focused on the gut microbiota's role in systemic diseases, the oral microbiome represents the second largest community of microorganisms, making it a new promising therapeutic target. Periodontitis and dental caries are considered the two main consequences of oral bacterial imbalance. Studies have shown that oral dysbiosis effects are not limited locally. Due to technological advancement, research identified oral bacterial species in heart valves. This evidence links oral dysbiosis with the development of valvular heart disease (VHD). This review focuses on describing the mechanism behind prolonged local inflammation and dysbiosis, that can induce bacteriemia by direct or immune-mediated mechanisms and finally VHD. Additionally, we highlight emerging therapies based on controlling oral dysbiosis, periodontal disease, and inflammation with immunological and systemic effects, that exert beneficial effects in VHD management.
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Affiliation(s)
- Ecaterina Neculae
- Department of Gastroenterology, “Grigore T. Popa” University of Medicine and Pharmacy, 700115 Iasi, Romania
- Institute of Gastroenterology and Hepatology, “Sf. Spiridon” County Clinical Emergency Hospital Iasi, 700111 Iasi, Romania
| | - Evelina Maria Gosav
- Department of Internal Medicine, “Grigore T. Popa” University of Medicine and Pharmacy, 700115 Iasi, Romania
- Internal Medicine Clinic, “St. Spiridon” County Clinical Emergency Hospital Iasi, 700111 Iasi, Romania
| | - Emilia Valasciuc
- Department of Internal Medicine, “Grigore T. Popa” University of Medicine and Pharmacy, 700115 Iasi, Romania
- Internal Medicine Clinic, “St. Spiridon” County Clinical Emergency Hospital Iasi, 700111 Iasi, Romania
| | - Nicoleta Dima
- Department of Internal Medicine, “Grigore T. Popa” University of Medicine and Pharmacy, 700115 Iasi, Romania
- Internal Medicine Clinic, “St. Spiridon” County Clinical Emergency Hospital Iasi, 700111 Iasi, Romania
| | - Mariana Floria
- Department of Internal Medicine, “Grigore T. Popa” University of Medicine and Pharmacy, 700115 Iasi, Romania
- Internal Medicine Clinic, “St. Spiridon” County Clinical Emergency Hospital Iasi, 700111 Iasi, Romania
- Correspondence:
| | - Daniela Maria Tanase
- Department of Internal Medicine, “Grigore T. Popa” University of Medicine and Pharmacy, 700115 Iasi, Romania
- Internal Medicine Clinic, “St. Spiridon” County Clinical Emergency Hospital Iasi, 700111 Iasi, Romania
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4
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Meng Y, Wang Q, Ma Z, Li W, Niu K, Zhu T, Lin H, Lu C, Fan H. Streptococcal autolysin promotes dysfunction of swine tracheal epithelium by interacting with vimentin. PLoS Pathog 2022; 18:e1010765. [PMID: 35921364 PMCID: PMC9377611 DOI: 10.1371/journal.ppat.1010765] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2022] [Revised: 08/15/2022] [Accepted: 07/25/2022] [Indexed: 11/24/2022] Open
Abstract
Streptococcus suis serotype 2 (SS2) is a major zoonotic pathogen resulting in manifestations as pneumonia and septic shock. The upper respiratory tract is typically thought to be the main colonization and entry site of SS2 in pigs, but the mechanism through which it penetrates the respiratory barrier is still unclear. In this study, a mutant with low invasive potential to swine tracheal epithelial cells (STECs) was screened from the TnYLB-1 transposon insertion mutant library of SS2, and the interrupted gene was identified as autolysin (atl). Compared to wild-type (WT) SS2, Δatl mutant exhibited lower ability to penetrate the tracheal epithelial barrier in a mouse model. Purified Atl also enhanced SS2 translocation across STEC monolayers in Transwell inserts. Furthermore, Atl redistributed the tight junctions (TJs) in STECs through myosin light chain kinase (MLCK) signaling, which led to increased barrier permeability. Using mass spectrometry, co-immunoprecipitation (co-IP), pull-down, bacterial two-hybrid and saturation binding experiments, we showed that Atl binds directly to vimentin. CRISPR/Cas9-targeted deletion of vimentin in STECs (VIM KO STECs) abrogated the capacity of SS2 to translocate across the monolayers, SS2-induced phosphorylation of myosin II regulatory light chain (MLC) and MLCK transcription, indicating that vimentin is indispensable for MLCK activation. Consistently, vimentin null mice were protected from SS2 infection and exhibited reduced tracheal and lung injury. Thus, MLCK-mediated epithelial barrier opening caused by the Atl-vimentin interaction is found to be likely the key mechanism by which SS2 penetrates the tracheal epithelium. Streptococcus suis serotype 2 (SS2), an emerging zoonotic agent, can breach the respiratory barrier and cause invasive disease in pigs. Here, we identified the novel role of autolysin Atl in penetration of the respiratory barrier by SS2 and its systemic dissemination and identified its binding partner, vimentin, a type III intermediate filament protein. Atl contributed to the MLCK-triggered redistribution of tight junctions to open the tracheal epithelial barrier. Knockout of vimentin abolished the ability of SS2 to penetrate the monolayer barrier and the activation of MLCK. Furthermore, vimentin null mice were protected from infection by intranasally administered SS2. This study is the first to demonstrate that the interaction between the GBS Bsp-like domain of Atl and vimentin promotes MLCK-mediated dysfunction of the epithelial barrier, which may provide theoretical information for prophylactic and/or therapeutic treatments against diseases caused by similar respiratory pathogens.
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Affiliation(s)
- Yu Meng
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - Qing Wang
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - Zhe Ma
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, China
| | - Weiyi Li
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - Kai Niu
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - Ting Zhu
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - Huixing Lin
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, China
| | - Chengping Lu
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, China
| | - Hongjie Fan
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, China
- * E-mail:
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Hsu CC, Hsu RB, Oon XH, Chen YT, Chen JW, Hsu CH, Kuo YM, Shih YH, Chia JS, Jung CJ. Streptococcus mutans PrsA mediates AtlA secretion contributing to extracellular DNA release and biofilm formation in the pathogenesis of infective endocarditis. Virulence 2022; 13:1379-1392. [PMID: 35876630 PMCID: PMC9377233 DOI: 10.1080/21505594.2022.2105351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
The role of secretion chaperone-regulated virulence proteins in the pathogenesis of infective endocarditis (IE) induced by viridans streptococci such as Streptococcus mutans is unclear. In this study, we investigated the contribution of the foldase protein PrsA, a putative parvulin-type peptidyl-prolyl isomerase, to the pathogenesis of S. mutans-induced IE. We found that a prsA-deficient strain had reduced virulence in terms of formation of vegetation on damaged heart valves, as well as reduced autolysis activity, eDNA release and biofilm formation capacity. The secretion and surface exposure of AtlA in vitro was reduced in the prsA-deficient mutant strain, and complementation of recombinant AtlA in the culture medium restored a wild type biofilm phenotype of the prsA-deficient mutant strain. This result suggests that secretion and surface localization of AtlA is regulated by PrsA during biofilm formation. Together, these results demonstrate that S. mutans PrsA could regulate AtlA-mediated eDNA release to contribute to biofilm formation in the pathogenesis of IE.
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Affiliation(s)
- Chih-Chieh Hsu
- Graduate Institute of Clinical Dentistry, School of Dentistry, National Taiwan University, Taipei, Taiwan.,Graduate Institute of Oral Biology, School of Dentistry, National Taiwan University, Taipei, Taiwan
| | - Ron-Bin Hsu
- Department of Surgery, Division of Cardiovascular Surgery, National Taiwan University Hospital , College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Xoong-Harng Oon
- Graduate Institute of Medical Sciences, College of Medicine, Taipei medical University, Taipei, Taiwan.,Department of Microbiology and Immunology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Ya-Tang Chen
- Graduate Institute of Medical Sciences, College of Medicine, Taipei medical University, Taipei, Taiwan
| | - Jeng-Wei Chen
- Department of Surgery, Division of Cardiovascular Surgery, National Taiwan University Hospital , College of Medicine, National Taiwan University, Taipei, Taiwan.,Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Che-Hao Hsu
- Graduate Institute of Medical Sciences, College of Medicine, Taipei medical University, Taipei, Taiwan
| | - Yu-Min Kuo
- Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan.,Division of Allergy, Immunology, and Rheumatology, Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan
| | - Yi-Hsien Shih
- Department of Dermatology, Taipei Medical University-Shuang Ho Hospital, New Taipei City, Taiwan.,Department of Dermatology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Jean-San Chia
- Graduate Institute of Medical Sciences, College of Medicine, Taipei medical University, Taipei, Taiwan.,Department of Microbiology and Immunology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Chiau-Jing Jung
- Graduate Institute of Medical Sciences, College of Medicine, Taipei medical University, Taipei, Taiwan.,Department of Microbiology and Immunology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
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6
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Hijacking host components for bacterial biofilm formation: An advanced mechanism. Int Immunopharmacol 2021; 103:108471. [PMID: 34952466 DOI: 10.1016/j.intimp.2021.108471] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 12/13/2021] [Accepted: 12/14/2021] [Indexed: 12/12/2022]
Abstract
Biofilm is a community of bacteria embedded in the extracellular matrix that accounts for 80% of bacterial infections. Biofilm enables bacterial cells to provide particular conditions and produce virulence determinants in response to the unavailability of micronutrients and local oxygen, resulting in their resistance to various antibacterial agents. Besides, the human immune reactions are not completely competent in the elimination of biofilm. Most importantly, the growing body of evidence shows that some bacterial spp. use a variety of mechanisms by which hijack the host components to form biofilm. In this regard, host components, such as DNA, hyaluronan, collagen, fibronectin, mucin, oligosaccharide moieties, filamentous polymers (F-actin), plasma, platelets, keratin, sialic acid, laminin, vitronectin, C3- and C4- binding proteins, antibody, proteases, factor I, factor H, and acidic proline-rich proteins have been reviewed. Hence, the characterization of interactions between bacterial biofilm and the host would be critical to effectively address biofilm-associated infections. In this paper, we review the latest information on the hijacking of host factors by bacteria to form biofilm.
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Fernandes Forte CP, Oliveira FAF, Lopes CDB, Alves APNN, Mota MRL, de Barros Silva PG, Montenegro RC, Campos Ribeiro Dos Santos ÂK, Lobo Filho JG, Sousa FB. Streptococcus mutans in atherosclerotic plaque: Molecular and immunohistochemical evaluations. Oral Dis 2021; 28:1705-1714. [PMID: 33825326 DOI: 10.1111/odi.13869] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Revised: 03/10/2021] [Accepted: 03/30/2021] [Indexed: 11/28/2022]
Abstract
OBJECTIVES To verify the presence of Streptococcus mutans (S. mutans) in atherosclerotic plaque (AP) using techniques with different sensitivities, correlating with histological changes in plaque and immunoexpression of inflammatory markers. MATERIALS AND METHODS Thirteen AP samples were subjected to real-time polymerase chain reaction (qRT-PCR), histopathological analyses, histochemical analysis by Giemsa staining (GS), and immunohistochemical analysis for S. mutans, IL-1β, and TNF-α (streptavidin-biotin-peroxidase method). Ten necropsy samples of healthy vessels were used as controls. RESULTS All AP samples showed histopathological characteristics of severe atherosclerosis and were positive for S. mutans (100.0%) in qRT-PCR and immunohistochemical analyses. GS showed that Streptococcus sp. colonized the lipid-rich core regions and fibrous tissue, while the control group was negative for Streptococcus sp. IL-1β and TNF-α were expressed in 100% and 92.3% of the AP tested, respectively. The control samples were positive for S. mutans in qRT-PCR analysis, but negative for S. mutans, IL-1β, and TNF-α in immunohistochemical analyses. CONCLUSION The detection of S. mutans in AP and the visualization of Streptococcus sp. suggested a possible association between S. mutans and atherosclerosis. The results obtained from the control samples suggested the presence of DNA fragments or innocuous bacteria that were not associated with tissue alteration. However, future studies are necessary to provide more information.
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Affiliation(s)
| | | | - Camile de Barros Lopes
- Department of Human and Medical Genetics, School of Biological Sciences, Federal University of Para, Belém, Brazil
| | | | - Mário Rogério Lima Mota
- Department of Stomatology and Oral Pathology, School of Dentistry, Federal University of Ceará, Fortaleza, Brazil
| | | | - Raquel Carvalho Montenegro
- Department of Human Cytogenetics, School of Biological Sciences, Federal University of Para, Belém, Brazil
| | | | | | - Fabrício Bitu Sousa
- Department of Stomatology and Oral Pathology, School of Dentistry, Federal University of Ceará, Fortaleza, Brazil
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Jung CJ, Hsu CC, Chen JW, Cheng HW, Yuan CT, Kuo YM, Hsu RB, Chia JS. PspC domain-containing protein (PCP) determines Streptococcus mutans biofilm formation through bacterial extracellular DNA release and platelet adhesion in experimental endocarditis. PLoS Pathog 2021; 17:e1009289. [PMID: 33577624 PMCID: PMC7906467 DOI: 10.1371/journal.ppat.1009289] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 02/25/2021] [Accepted: 01/07/2021] [Indexed: 11/19/2022] Open
Abstract
Bacterial extracellular DNA (eDNA) and activated platelets have been found to contribute to biofilm formation by Streptococcus mutans on injured heart valves to induce infective endocarditis (IE), yet the bacterial component directly responsible for biofilm formation or platelet adhesion remains unclear. Using in vivo survival assays coupled with microarray analysis, the present study identified a LiaR-regulated PspC domain-containing protein (PCP) in S. mutans that mediates bacterial biofilm formation in vivo. Reverse transcriptase- and chromatin immunoprecipitation-polymerase chain reaction assays confirmed the regulation of pcp by LiaR, while PCP is well-preserved among streptococcal pathogens. Deficiency of pcp reduced in vitro and in vivo biofilm formation and released the eDNA inside bacteria floe along with reduced bacterial platelet adhesion capacity in a fibrinogen-dependent manner. Therefore, LiaR-regulated PCP alone could determine release of bacterial eDNA and binding to platelets, thus contributing to biofilm formation in S. mutans-induced IE.
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Affiliation(s)
- Chiau-Jing Jung
- Department of Microbiology and Immunology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Chih-Chieh Hsu
- Graduate Institute of Oral Biology, School of Dentistry, National Taiwan University, Taipei, Taiwan
| | - Jeng-Wei Chen
- Division of Cardiovascular Surgery, Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan
- Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Hung-Wei Cheng
- Graduate Institute of Microbiology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Chang-Tsu Yuan
- Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan
- Department of Pathology, National Taiwan University Cancer Center, Taipei, Taiwan
- Department of Pathology, National Taiwan University Hospital, Taipei, Taiwan
| | - Yu-Min Kuo
- Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Ron-Bin Hsu
- Division of Cardiovascular Surgery, Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan
| | - Jean-San Chia
- Graduate Institute of Oral Biology, School of Dentistry, National Taiwan University, Taipei, Taiwan
- Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan
- Graduate Institute of Immunology, College of Medicine, National Taiwan University, Taipei, Taiwan
- * E-mail:
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9
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Alves LA, Ganguly T, Harth-Chú ÉN, Kajfasz J, Lemos JA, Abranches J, Mattos-Graner RO. PepO is a target of the two-component systems VicRK and CovR required for systemic virulence of Streptococcus mutans. Virulence 2020; 11:521-536. [PMID: 32427040 PMCID: PMC7239026 DOI: 10.1080/21505594.2020.1767377] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Revised: 03/10/2020] [Accepted: 03/29/2020] [Indexed: 12/14/2022] Open
Abstract
Streptococcus mutans, a cariogenic species, is often associated with cardiovascular infections. Systemic virulence of specific S. mutans serotypes has been associated with the expression of the collagen- and laminin-binding protein Cnm, which is transcriptionally regulated by VicRK and CovR. In this study, we characterized a VicRK- and CovR-regulated gene, pepO, coding for a conserved endopeptidase. Transcriptional and protein analyses revealed that pepO is highly expressed in S. mutans strains resistant to complement immunity (blood isolates) compared to oral isolates. Gel mobility assay, transcriptional, and Western blot analyses revealed that pepO is repressed by VicR and induced by CovR. Deletion of pepO in the Cnm+ strain OMZ175 (OMZpepO) or in the Cnm- UA159 (UApepO) led to an increased susceptibility to C3b deposition, and to low binding to complement proteins C1q and C4BP. Additionally, pepO mutants showed diminished ex vivo survival in human blood and impaired capacity to kill G. mellonella larvae. Inactivation of cnm in OMZ175 (OMZcnm) resulted in increased resistance to C3b deposition and unaltered blood survival, although both pepO and cnm mutants displayed attenuated virulence in G. mellonella. Unlike OMZcnm, OMZpepO could invade HCAEC endothelial cells. Supporting these phenotypes, recombinant proteins rPepO and rCnmA showed specific profiles of binding to C1q, C4BP, and to other plasma (plasminogen, fibronectin) and extracellular matrix proteins (type I collagen, laminin). Therefore this study identifies a novel VicRK/CovR-target required for immune evasion and host persistence, pepO, expanding the roles of VicRK and CovR in regulating S. mutans virulence.
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Affiliation(s)
- Lívia A. Alves
- Department of Oral Diagnosis, Piracicaba Dental School – State University of Campinas, Piracicaba, SP, Brazil
| | - Tridib Ganguly
- Department of Oral Biology, University of Florida College of Dentistry, Gainesville, FL, USA
| | - Érika N. Harth-Chú
- Department of Oral Diagnosis, Piracicaba Dental School – State University of Campinas, Piracicaba, SP, Brazil
| | - Jessica Kajfasz
- Department of Oral Biology, University of Florida College of Dentistry, Gainesville, FL, USA
| | - José A. Lemos
- Department of Oral Biology, University of Florida College of Dentistry, Gainesville, FL, USA
| | - Jacqueline Abranches
- Department of Oral Biology, University of Florida College of Dentistry, Gainesville, FL, USA
| | - Renata O. Mattos-Graner
- Department of Oral Diagnosis, Piracicaba Dental School – State University of Campinas, Piracicaba, SP, Brazil
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10
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Balasubramanian AR, Vasudevan S, Shanmugam K, Lévesque CM, Solomon AP, Neelakantan P. Combinatorial effects of trans-cinnamaldehyde with fluoride and chlorhexidine on Streptococcus mutans. J Appl Microbiol 2020; 130:382-393. [PMID: 32707601 DOI: 10.1111/jam.14794] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 07/06/2020] [Accepted: 07/18/2020] [Indexed: 01/03/2023]
Abstract
AIMS The aim of this study was to investigate the effects of trans-cinnamaldehyde (TC) and its synergistic activity with chlorhexidine (CHX) and fluoride against Streptococcus mutans. METHODS AND RESULTS Streptococcus mutans UA159 was treated with TC alone and in combination with CHX or sodium fluoride. The synergy profile was analysed using the Zero Interaction Potency model. TC showed strong synergism (synergy score of 21·697) with CHX, but additive effect (synergy score of 5·298) with fluoride. TC and the combinations were tested for acid production (glycolytic pH drop) and biofilm formation by S. mutans, and nitric oxide production in macrophages. TC significantly inhibited sucrose-dependent biofilm formation and acid production by S. mutans. Mechanistic studies were carried out by qRT-PCR-based transcriptomic studies which showed that TC acts by impairing genes related to metabolism, quorum sensing, bacteriocin expression, stress tolerance and biofilm formation. CONCLUSIONS trans-Cinnamaldehyde potentiates CHX and sodium fluoride in inhibiting S. mutans biofilms and virulence through multiple mechanisms. This study sheds significant new light on the potential to develop TC as an anti-caries treatment. SIGNIFICANCE AND IMPACT OF THE STUDY Oral diseases were classified as a 'silent epidemic' in the US Surgeon General's Report on Oral Health. Two decades later, >4 billion people are still affected worldwide by caries, having significant effects on the quality of life. There is an urgent need to develop novel compounds and strategies to combat dental caries. Here, we prove that TC downregulates multiple pathways and potentiates the CHX and fluoride to prevent S. mutans biofilms and virulence. This study sheds significant new light on the potential to develop TC in combination with CHX or fluoride as novel treatments to arrest dental caries.
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Affiliation(s)
- A R Balasubramanian
- Quorum Sensing Laboratory, Centre for Research in Infectious Diseases (CRID), School of Chemical and Biotechnology, SASTRA Deemed to be University, Thanjavur, India
| | - S Vasudevan
- Quorum Sensing Laboratory, Centre for Research in Infectious Diseases (CRID), School of Chemical and Biotechnology, SASTRA Deemed to be University, Thanjavur, India
| | - K Shanmugam
- Quorum Sensing Laboratory, Centre for Research in Infectious Diseases (CRID), School of Chemical and Biotechnology, SASTRA Deemed to be University, Thanjavur, India
| | - C M Lévesque
- Faculty of Dentistry, University of Toronto, Toronto, ON, Canada
| | - A P Solomon
- Quorum Sensing Laboratory, Centre for Research in Infectious Diseases (CRID), School of Chemical and Biotechnology, SASTRA Deemed to be University, Thanjavur, India
| | - P Neelakantan
- Faculty of Dentistry, The University of Hong Kong, Hong Kong, Hong Kong SAR
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11
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Lu J, Francis J, Doster RS, Haley KP, Craft KM, Moore RE, Chambers SA, Aronoff DM, Osteen K, Damo SM, Manning S, Townsend SD, Gaddy JA. Lactoferrin: A Critical Mediator of Both Host Immune Response and Antimicrobial Activity in Response to Streptococcal Infections. ACS Infect Dis 2020; 6:1615-1623. [PMID: 32329605 DOI: 10.1021/acsinfecdis.0c00050] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Streptococcal species are Gram-positive bacteria responsible for a variety of disease outcomes including pneumonia, meningitis, endocarditis, erysipelas, necrotizing fasciitis, periodontitis, skin and soft tissue infections, chorioamnionitis, premature rupture of membranes, preterm birth, and neonatal sepsis. In response to streptococcal infections, the host innate immune system deploys a repertoire of antimicrobial and immune modulating molecules. One important molecule that is produced in response to streptococcal infections is lactoferrin. Lactoferrin has antimicrobial properties including the ability to bind iron with high affinity and sequester this important nutrient from an invading pathogen. Additionally, lactoferrin has the capacity to alter the host inflammatory response and contribute to disease outcome. This Review presents the most recent published work that studies the interaction between the host innate immune protein lactoferrin and the invading pathogen, Streptococcus.
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Affiliation(s)
- Jacky Lu
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee 37232, United States
| | - Jamisha Francis
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee 37232, United States
| | - Ryan S. Doster
- Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee 37232, United States
| | - Kathryn P. Haley
- Department of Biomedical Sciences, Grand Valley State University, Allendale, Michigan 49401, United States
| | - Kelly M. Craft
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37232, United States
| | - Rebecca E. Moore
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37232, United States
| | - Schuyler A. Chambers
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37232, United States
| | - David M. Aronoff
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee 37232, United States
- Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee 37232, United States
| | - Kevin Osteen
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee 37232, United States
- Department of Veterans Affairs, Tennessee Valley Healthcare Systems, Nashville, Tennessee 37212, United States
- Department of Obstetrics and Gynecology, Vanderbilt University Medical Center, Nashville, Tennessee 37232, United States
| | - Steven M. Damo
- Department of Chemistry, Fisk University, Nashville, Tennessee 37208, United States
- Department of Biochemistry, Vanderbilt University, Nashville, Tennessee 37232, United States
| | - Shannon Manning
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, Michigan 48824, United States
| | - Steven D. Townsend
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37232, United States
| | - Jennifer A. Gaddy
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee 37232, United States
- Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee 37232, United States
- Department of Veterans Affairs, Tennessee Valley Healthcare Systems, Nashville, Tennessee 37212, United States
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12
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Chen H, Tang Y, Weir MD, Gao J, Imazato S, Oates TW, Lei L, Wang S, Hu T, Xu HHK. Effects of S. mutans gene-modification and antibacterial monomer dimethylaminohexadecyl methacrylate on biofilm growth and acid production. Dent Mater 2019; 36:296-309. [PMID: 31839202 DOI: 10.1016/j.dental.2019.12.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Revised: 08/17/2019] [Accepted: 12/02/2019] [Indexed: 02/05/2023]
Abstract
OBJECTIVES Antibacterial quaternary ammonium monomers (QAMs) are used in resins. The rnc gene in Streptococcus mutans (S. mutans) plays a key role in resisting antibiotics. The objectives of this study were to investigate for the first time: (1) the effects of rnc deletion on S. mutans biofilms and acid production; (2) the combined effects of rnc deletion with dimethylaminohexadecyl methacrylate (DMAHDM) on biofilm-inhibition efficacy. METHODS Parent S. mutans strain UA159 (ATCC 700610) and the rnc-deleted S. mutans were used. Bacterial growth, minimum inhibitory concentration (MIC), and minimal bactericidal concentration (MBC) were measured to analyze the bacterial susceptibility of the parent and rnc-deleted S. mutans against DMAHDM, with the gold-standard chlorhexidine (CHX) as control. Biofilm biomass, polysaccharide and lactic acid production were measured. RESULTS The drug-susceptibility of the rnc-deleted S. mutans to DMAHDM or CHX was 2-fold higher than parent S. mutans. The drug-susceptibility did not increase after 10 passages (p < 0.05). Deleting the rnc gene increased the biofilm susceptibility to DMAHDM or CHX by 2-fold. The rnc-deletion in S. mutans reduced biofilm biomass, polysaccharide and lactic acid production, even at no drugs. DMAHDM was nearly 40 % more potent than the gold-standard CHX. The combination of rnc deletion+DMAHDM treatment achieved the greatest reduction in biofilm biomass, polysaccharide synthesis, and lactic acid production. SIGNIFICANCE Gene modification by deleting the rnc in S. mutans reduced the biofilm growth and acid production, and the rnc deletion+DMAHDM method showed the greatest biofilm-inhibition efficacy, for the first time. The dual strategy of antibacterial monomer+bacterial gene modification shows great potential to control biofilms and inhibit caries.
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Affiliation(s)
- Hong Chen
- State Key Laboratory of Oral Diseases, Department of Preventive Dentistry, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan 610041, China; Department of Advanced Oral Sciences and Therapeutics, University of Maryland Dental School, Baltimore, MD 21201, USA
| | - Yunhao Tang
- Department of Gastrointestinal Surgery, the Second Affiliated Hospital of Chongqing Medical University, Chongqing, 400010, China
| | - Michael D Weir
- Department of Advanced Oral Sciences and Therapeutics, University of Maryland Dental School, Baltimore, MD 21201, USA
| | - Jianghong Gao
- Department of Advanced Oral Sciences and Therapeutics, University of Maryland Dental School, Baltimore, MD 21201, USA; Clinical Research Center of Shaanxi Province for Dental and Maxillofacial Diseases, Department of Preventive Dentistry, College of Stomatology, Xi'an Jiaotong University, Xi'an, 710004, China
| | - Satoshi Imazato
- Department of Biomaterials Science, Osaka University Graduate School of Dentistry, Osaka, Japan
| | - Thomas W Oates
- Department of Advanced Oral Sciences and Therapeutics, University of Maryland Dental School, Baltimore, MD 21201, USA
| | - Lei Lei
- State Key Laboratory of Oral Diseases, Department of Preventive Dentistry, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan 610041, China
| | - Suping Wang
- Department of Advanced Oral Sciences and Therapeutics, University of Maryland Dental School, Baltimore, MD 21201, USA; Department of Operative Dentistry and Endodontics & Periodontics and Stomatology Center, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, Henan, China.
| | - Tao Hu
- State Key Laboratory of Oral Diseases, Department of Preventive Dentistry, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan 610041, China.
| | - Hockin H K Xu
- Department of Advanced Oral Sciences and Therapeutics, University of Maryland Dental School, Baltimore, MD 21201, USA; Center for Stem Cell Biology & Regenerative Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, USA; Marlene and Stewart Greenebaum Cancer Center, University of Maryland School of Medicine, Baltimore, MD 21201, USA.
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13
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Matysik A, Ho FK, Ler Tan AQ, Vajjala A, Kline KA. Cellular chaining influences biofilm formation and structure in group A Streptococcus. Biofilm 2019; 2:100013. [PMID: 33447800 PMCID: PMC7798446 DOI: 10.1016/j.bioflm.2019.100013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 11/02/2019] [Accepted: 11/22/2019] [Indexed: 11/16/2022] Open
Abstract
Group A Streptococcal (GAS) biofilm formation is an important pathological feature contributing to the antibiotic tolerance and progression of various GAS infections. Although a number of bacterial factors have been described to promote in vitro GAS biofilm formation, the relevance of in vitro biofilms to host-associated biofilms requires further understanding. In this study, we demonstrate how constituents of the host environment, such as lysozyme and NaCl, can modulate GAS bacterial chain length and, in turn, shape GAS biofilm morphology and structure. Disruption of GAS chains with lysozyme results in biofilms that are more stable. Based on confocal microscopy, we attribute the increase in biofilm stability to a dense and compact three-dimensional structure produced by de-chained cells. To show that changes in biofilm stability and structure are due to the shortening of bacterial chains and not specific to the activity of lysozyme, we demonstrate that augmented chaining induced by NaCl or deletion of the autolysin gene mur1.2 produced defects in biofilm formation characterized by a loose biofilm architecture. We conclude that GAS biofilm formation can be directly influenced by host and environmental factors through the modulation of bacterial chain length, potentially contributing to persistence and colonization within the host. Further studies of in vitro biofilm models incorporating physiological constituents such as lysozyme may uncover new insights into the physiology of in vivo GAS biofilms.
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Affiliation(s)
- Artur Matysik
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, 60 Nanyang Dr, 637551, Singapore
| | - Foo Kiong Ho
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, 60 Nanyang Dr, 637551, Singapore
| | - Alicia Qian Ler Tan
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, 60 Nanyang Dr, 637551, Singapore
| | - Anuradha Vajjala
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, 60 Nanyang Dr, 637551, Singapore
| | - Kimberly A Kline
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, 60 Nanyang Dr, 637551, Singapore.,School of Biological Sciences, Nanyang Technological University, 60 Nanyang Dr, Singapore, 637551
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14
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Oliveira FAF, Fernandes Forte CP, Silva PGDB, Lopes CDB, Montenegro RC, Dos Santos ÂKCR, Mota MRL, Sousa FB, Alves APNN. Relationship of Streptococcus mutans with valvar cardiac tissue: A molecular and immunohistochemical study. J Oral Pathol Med 2019; 48:745-753. [PMID: 31323147 DOI: 10.1111/jop.12929] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2019] [Revised: 06/04/2019] [Accepted: 07/04/2019] [Indexed: 11/30/2022]
Abstract
BACKGROUND The present study aimed to investigate the presence or absence of Streptococcus mutans in oral cavity and valvular samples associating with the histomorphologic alterations of calcified aortic stenosis. METHODOLOGY Dental plaque and cardiac valve samples were collected from 10 patients with calcified aortic stenosis for molecular analysis of S mutans by real-time polymerase chain reaction (PCR). Healthy valve tissue was also collected from five young cadavers and analyzed for S mutans. Moreover, fragments of all valvar specimens were submitted for histomorphological analysis and immunohistochemistry (anti-S mutans and anti-CD61). RESULTS Streptococcus mutans was present in 100% of the oral cavity samples from the patients with calcified aortic stenosis in the molecular analysis. The analysis by real-time PCR showed that S mutans presented the same proportion in healthy valves and those with calcified aortic stenosis (80%; P = 1.000). Conversely, the immunoexpression of S mutans was 37.40 (IC95% = 1.49-937.00) times superior in samples of patients with cardiac disease (P = .007). The immunoexpression analysis showed that CD61 was present in seven (70%) calcified aortic stenosis samples, all of which were also immunopositive for S mutans. CONCLUSIONS Streptococcus mutans was found in the oral cavity, healthy valve tissue, and calcified aortic stenosis samples. However, the microorganism was visualized by immunohistochemistry only in the calcified aortic stenosis samples, which may suggest viability and an increased bacterial density in this condition. The association of the presence of S mutans and positive CD61 immunoexpression suggests a probable relationship with calcified aortic stenosis.
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Affiliation(s)
- Francisco Artur Forte Oliveira
- Department of Stomatology and Oral Pathology, School of Dentistry, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | | | | | - Camile de Barros Lopes
- Laboratory of Human and Medical Genetics, Graduate Program in Genetics and Molecular Biology, Federal University of Pará, Brazil
| | - Raquel Carvalho Montenegro
- Department of Human Cytogenetics, School of Biological Sciences, Federal University of Para, Belém, Pará, Brazil
| | | | - Mário Rogério Lima Mota
- Department of Stomatology and Oral Pathology, School of Dentistry, Federal University of Ceará, Fortaleza, Ceará, Brazil.,Department of Oral Pathology, School of Dentistry, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | - Fabrício Bitu Sousa
- Department of Stomatology and Oral Pathology, School of Dentistry, Federal University of Ceará, Fortaleza, Ceará, Brazil.,Department of Oral Pathology, School of Dentistry, Federal University of Ceará, Fortaleza, Ceará, Brazil
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15
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CovR and VicRKX Regulate Transcription of the Collagen Binding Protein Cnm of Streptococcus mutans. J Bacteriol 2018; 200:JB.00141-18. [PMID: 30201780 DOI: 10.1128/jb.00141-18] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2018] [Accepted: 09/04/2018] [Indexed: 11/20/2022] Open
Abstract
Cnm is a surface-associated protein present in a subset of Streptococcus mutans strains that mediates binding to extracellular matrices, intracellular invasion, and virulence. Here, we showed that cnm transcription is controlled by the global regulators CovR and VicRKX. In silico analysis identified multiple putative CovR- and VicR-binding motifs in the regulatory region of cnm as well as in the downstream gene pgfS, which is associated with the posttranslational modification of Cnm. Electrophoretic mobility shift assays revealed that CovR and VicR specifically and independently bind to the cnm and pgfS promoter regions. Quantitative real-time PCR and Western blot analyses of ΔcovR and ΔvicK strains as well as of a strain overexpressing vicRKX revealed that CovR functions as a positive regulator of cnm, whereas VicRKX acts as a negative regulator. In agreement with the role of VicRKX as a repressor, the ΔvicK strain showed enhanced binding to collagen and laminin and higher intracellular invasion rates. Overexpression of vicRKX was associated with decreased rates of intracellular invasion but did not affect collagen or lamin binding activities, suggesting that this system controls additional genes involved in binding to these extracellular matrix proteins. As expected, based on the role of CovR in cnm regulation, the ΔcovR strain showed decreased intracellular invasion rates, but, unexpectedly collagen and laminin binding activities were increased in this mutant strain. Collectively, the results presented here expand the repertoire of virulence-related genes regulated by CovR and VicRKX to include the core gene pgfS and the noncore gene cnm IMPORTANCE Streptococcus mutans is a major pathogen associated with dental caries and also implicated in systemic infections, in particular, infective endocarditis. The Cnm adhesin of S. mutans is an important virulence factor associated with systemic infections and caries severity. Despite its role in virulence, the regulatory mechanisms governing cnm expression are poorly understood. Here, we describe the identification of two independent regulatory systems controlling the transcription of cnm and the downstream pgfS-pgfM1-pgfE-pgfM2 operon. A better understanding of the mechanisms controlling expression of virulence factors like Cnm can facilitate the development of new strategies to treat bacterial infections.
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16
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Kodama Y, Ishikawa T, Shimoyama Y, Sasaki D, Kimura S, Sasaki M. The fibronectin-binding protein homologue Fbp62 ofStreptococcus anginosusis a potent virulence factor. Microbiol Immunol 2018; 62:624-634. [DOI: 10.1111/1348-0421.12646] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Revised: 08/15/2018] [Accepted: 09/04/2018] [Indexed: 11/28/2022]
Affiliation(s)
- Yoshitoyo Kodama
- Division of Molecular Microbiology; Department of Microbiology; Iwate Medical University; 2-1-1 Nishitokuta Yahaba-cho Shiwagun Iwate 028-3694 Japan
| | - Taichi Ishikawa
- Division of Molecular Microbiology; Department of Microbiology; Iwate Medical University; 2-1-1 Nishitokuta Yahaba-cho Shiwagun Iwate 028-3694 Japan
| | - Yu Shimoyama
- Division of Molecular Microbiology; Department of Microbiology; Iwate Medical University; 2-1-1 Nishitokuta Yahaba-cho Shiwagun Iwate 028-3694 Japan
| | - Daisuke Sasaki
- Division of Periodontology; Department of Conservative Dentistry; Iwate Medical University School of Dentistry; 1-3-27 Chuo-dori Morioka Iwate 020-8505 Japan
| | - Shigenobu Kimura
- Division of Molecular Microbiology; Department of Microbiology; Iwate Medical University; 2-1-1 Nishitokuta Yahaba-cho Shiwagun Iwate 028-3694 Japan
| | - Minoru Sasaki
- Division of Molecular Microbiology; Department of Microbiology; Iwate Medical University; 2-1-1 Nishitokuta Yahaba-cho Shiwagun Iwate 028-3694 Japan
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17
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Jeffery C. Intracellular proteins moonlighting as bacterial adhesion factors. AIMS Microbiol 2018; 4:362-376. [PMID: 31294221 PMCID: PMC6604927 DOI: 10.3934/microbiol.2018.2.362] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 05/22/2018] [Indexed: 02/06/2023] Open
Abstract
Pathogenic and commensal, or probiotic, bacteria employ adhesins on the cell surface to attach to and interact with the host. Dozens of the adhesins that play key roles in binding to host cells or extracellular matrix were originally identified as intracellular chaperones or enzymes in glycolysis or other central metabolic pathways. Proteins that have two very different functions, often in two different subcellular locations, are referred to as moonlighting proteins. The intracellular/surface moonlighting proteins do not contain signal sequences for secretion or known sequence motifs for binding to the cell surface, so in most cases is not known how these proteins are secreted or how they become attached to the cell surface. A secretion system in which a large portion of the pool of each protein remains inside the cell while some of the pool of the protein is partitioned to the cell surface has not been identified. This may involve a novel version of a known secretion system or it may involve a novel secretion system. Understanding the processes by which intracellular/cell surface moonlighting proteins are targeted to the cell surface could provide novel protein targets for the development of small molecules that block secretion and/or association with the cell surface and could serve as lead compounds for the development of novel antibacterial therapeutics.
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Affiliation(s)
- Constance Jeffery
- Department of Biological Sciences, University of Illinois at Chicago, 900 S Ashland Ave, Chicago, IL 60607, USA
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18
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Macrophage Polarization Alters Postphagocytosis Survivability of the Commensal Streptococcus gordonii. Infect Immun 2018; 86:IAI.00858-17. [PMID: 29229734 DOI: 10.1128/iai.00858-17] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Accepted: 12/05/2017] [Indexed: 12/22/2022] Open
Abstract
Oral streptococci are generally considered commensal organisms; however, they are becoming recognized as important associate pathogens during the development of periodontal disease as well as being associated with several systemic diseases, including as a causative agent of infective endocarditis. An important virulence determinant of these bacteria is an ability to evade destruction by phagocytic cells, yet how this subversion occurs is mostly unknown. Using Streptococcus gordonii as a model commensal oral streptococcus that is also associated with disease, we find that resistance to reactive oxygen species (ROS) with an active ability to damage phagosomes allows the bacterium to avoid destruction within macrophages. This ability to survive relies not only on the ROS resistance capabilities of the bacterium but also on ROS production by macrophages, with both being required for maximal survival of internalized bacteria. Importantly, we also show that this dependence on ROS production by macrophages for resistance has functional significance: S. gordonii intracellular survival increases when macrophages are polarized toward an activated (M1) profile, which is known to result in prolonged phagosomal ROS production compared to that of alternatively (M2) polarized macrophages. We additionally find evidence of the bacterium being capable of both delaying the maturation of and damaging phagosomes. Taken together, these results provide essential insights regarding the mechanisms through which normally commensal oral bacteria can contribute to both local and systemic inflammatory disease.
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19
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Grimm I, Dumke J, Dreier J, Knabbe C, Vollmer T. Biofilm formation and transcriptome analysis of Streptococcus gallolyticus subsp. gallolyticus in response to lysozyme. PLoS One 2018; 13:e0191705. [PMID: 29373594 PMCID: PMC5786311 DOI: 10.1371/journal.pone.0191705] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Accepted: 01/10/2018] [Indexed: 02/06/2023] Open
Abstract
Streptococcus gallolyticus subsp. gallolyticus is a commensal bacterium of the human gastrointestinal tract, and a pathogen causing infective endocarditis and other biofilm-associated infections via exposed collagen. This study focuses on the characterization of the biofilm formation and collagen adhesion of S. gallolyticus subsp. gallolyticus under different conditions. In this study, it has been observed that the isolate UCN 34 is resistant to 20 mg/ml lysozyme in BHI medium, whereas the strain BAA-2069 builds more biofilm in the presence of lysozyme compared to in a control of BHI without lysozyme. A transcriptome analysis with whole genome microarrays of these two isolates in BHI medium with lysozyme compared to control without lysozyme revealed changes in gene expression levels. In the isolate BAA-2069, 67 genes showed increased expression in the presence of lysozyme, while in the isolate UCN 34, 165 genes showed increased expression and 30 genes showed decreased expression through lysozyme treatment. Products of genes which were higher expressed are in involved in transcription and translation, in cell-wall modification, in hydrogen peroxide resistance and in bacterial immunity. Furthermore, the adhesion ability of different strains of S. gallolyticus subsp. gallolyticus to collagen type I and IV was analyzed. Thereby, we compared the adhesion of 46 human isolates with 23 isolates from animals. It was shown that the adhesion ability depends significantly on whether the isolate was isolated from human or animal. For example, high adhesion ability was observed for strain UCN 34 isolated from an infective endocarditis patient, whereas strain DSM 16831 isolated from koala feces adhered only marginally to collagen. Full genome microarray analysis of these two strains revealed strain-dependent gene expression due to adhesion. The expression of 25 genes of a transposon and 15 genes of a phage region in strain DSM 16831 were increased, which corresponds to horizontal gene transfer. Adherence to collagen in strain UCN 34 led to higher expression of 27 genes and lower expression of 31 genes. This was suggestive of a change in nutrient uptake.
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Affiliation(s)
- Imke Grimm
- Institut für Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinikum der Ruhr-Universität Bochum, Bad Oeynhausen, Germany
| | - Jessika Dumke
- Institut für Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinikum der Ruhr-Universität Bochum, Bad Oeynhausen, Germany
| | - Jens Dreier
- Institut für Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinikum der Ruhr-Universität Bochum, Bad Oeynhausen, Germany
| | - Cornelius Knabbe
- Institut für Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinikum der Ruhr-Universität Bochum, Bad Oeynhausen, Germany
| | - Tanja Vollmer
- Institut für Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinikum der Ruhr-Universität Bochum, Bad Oeynhausen, Germany
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20
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Grimm I, Weinstock M, Birschmann I, Dreier J, Knabbe C, Vollmer T. Strain-dependent interactions of Streptococcus gallolyticus subsp. gallolyticus with human blood cells. BMC Microbiol 2017; 17:210. [PMID: 29078765 PMCID: PMC5658974 DOI: 10.1186/s12866-017-1116-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Accepted: 10/18/2017] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Streptococcus gallolyticus subsp. gallolyticus (S. gallolyticus) is the causative pathogen in up to 20% of streptococcal-induced infective endocarditis (IE) cases. However, the underlying mechanisms of pathogenesis in S. gallolyticus have not yet been solved. Pathogens causing IE need to employ virulent strategies to initiate and establish infections, such as escape the bloodstream, invade the host-cell, and persist intracellularly. In this study, we examined the induction of inflammation by different S. gallolyticus strains in relation to their survival in whole blood and cell culture models as well as their ability to induce platelet aggregation. Phagocytosis of these bacteria by macrophages, followed by intracellular survival, was also quantified. METHODS In whole blood and THP-1 cell culture assays bacterial growth kinetics was determined by plating, followed by colony counting. Induction of interleukin (IL)-6 expression in whole blood of three healthy volunteers, caused by different strains, was quantified by ELISA. Gene expression of cytokines (IL1B, IL6 and IL8) was quantified by real-time PCR after stimulating THP-1 monocytes with bacteria. Induction of platelet aggregation was analyzed by light transmission aggregometry using the BORN method. A macrophage model was used to analyze phagocytosis of strains and their survival in macrophages within 48 h. RESULTS Strains promoted IL-6 secretion in a time-dependent fashion. For example, DSM16831 induced IL-6 secretion in whole blood earlier than other isolates, and was eliminated in the whole blood of one volunteer, whereas UCN34 could grow. Platelet aggregation depended on the different isolates used and on the individual platelet donor. Two strains (AC1181 and 010672/01) induced cytokine gene expression in THP-1 monocytes only marginally, compared to other strains. The phagocytosis rate of S. gallolyticus isolates differed significantly, and the isolates UCN34 and BAA-2069 could persist for a considerable time in the phagocytes. CONCLUSION The strain-dependent differences of S. gallolyticus isolates, observed during interaction with human blood cells, support the hypotheses that divergences in individual virulence factors determine a distinct pathogenicity of the isolates. These data constitute an additional step towards the elucidation of mechanisms in the complex, multifactorial pathogenesis of this IE pathogen.
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Affiliation(s)
- Imke Grimm
- Institut für Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinikum der Ruhr-Universität Bochum, Bad Oeynhausen, Germany
| | - Melanie Weinstock
- Institut für Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinikum der Ruhr-Universität Bochum, Bad Oeynhausen, Germany
| | - Ingvild Birschmann
- Institut für Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinikum der Ruhr-Universität Bochum, Bad Oeynhausen, Germany
| | - Jens Dreier
- Institut für Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinikum der Ruhr-Universität Bochum, Bad Oeynhausen, Germany
| | - Cornelius Knabbe
- Institut für Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinikum der Ruhr-Universität Bochum, Bad Oeynhausen, Germany
| | - Tanja Vollmer
- Institut für Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinikum der Ruhr-Universität Bochum, Bad Oeynhausen, Germany.
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Remodeling of the Streptococcus mutans proteome in response to LrgAB and external stresses. Sci Rep 2017; 7:14063. [PMID: 29070798 PMCID: PMC5656683 DOI: 10.1038/s41598-017-14324-w] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Accepted: 10/09/2017] [Indexed: 11/24/2022] Open
Abstract
The Streptococcus mutans Cid/Lrg system represents an ideal model to study how this organism withstands various stressors encountered in the oral cavity. Mutation of lrgAB renders S. mutans more sensitive to oxidative, heat, and vancomycin stresses. Here, we have performed a comprehensive proteomics experiment using label-free quantitative mass spectrometry to compare the proteome changes of wild type UA159 and lrgAB mutant strains in response to these same stresses. Importantly, many of identified proteins showed either a strikingly large fold-change, or were completely suppressed or newly induced in response to a particular stress condition. Notable stress proteome changes occurred in a variety of functional categories, including amino acid biosynthesis, energy metabolism, protein synthesis, transport/binding, and transcriptional/response regulators. In the non-stressed growth condition, mutation of lrgAB significantly altered the abundance of 76 proteins (a fold change >1.4, or <0.6, p-value <0.05) and several of these matched the stress proteome of the wild type strain. Interestingly, the statistical correlation between the proteome changes and corresponding RNA-seq transcriptomic studies was relatively low (rho(ρ) <0.16), suggesting that adaptation to a new environment may require radical proteome turnover or metabolic remodeling. Collectively, this study reinforces the importance of LrgAB to the S. mutans stress response.
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AtlA Mediates Extracellular DNA Release, Which Contributes to Streptococcus mutans Biofilm Formation in an Experimental Rat Model of Infective Endocarditis. Infect Immun 2017; 85:IAI.00252-17. [PMID: 28674029 DOI: 10.1128/iai.00252-17] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Accepted: 06/23/2017] [Indexed: 12/23/2022] Open
Abstract
Host factors, such as platelets, have been shown to enhance biofilm formation by oral commensal streptococci, inducing infective endocarditis (IE), but how bacterial components contribute to biofilm formation in vivo is still not clear. We demonstrated previously that an isogenic mutant strain of Streptococcus mutans deficient in autolysin AtlA (ΔatlA) showed a reduced ability to cause vegetation in a rat model of bacterial endocarditis. However, the role of AtlA in bacterial biofilm formation is unclear. In this study, confocal laser scanning microscopy analysis showed that extracellular DNA (eDNA) was embedded in S. mutans GS5 floes during biofilm formation on damaged heart valves, but an ΔatlA strain could not form bacterial aggregates. Semiquantification of eDNA by PCR with bacterial 16S rRNA primers demonstrated that the ΔatlA mutant strain produced dramatically less eDNA than the wild type. Similar results were observed with in vitro biofilm models. The addition of polyanethol sulfonate, a chemical lysis inhibitor, revealed that eDNA release mediated by bacterial cell lysis is required for biofilm initiation and maturation in the wild-type strain. Supplementation of cultures with calcium ions reduced wild-type growth but increased eDNA release and biofilm mass. The effect of calcium ions on biofilm formation was abolished in ΔatlA cultures and by the addition of polyanethol sulfonate. The VicK sensor, but not CiaH, was found to be required for the induction of eDNA release or the stimulation of biofilm formation by calcium ions. These data suggest that calcium ion-regulated AtlA maturation mediates the release of eDNA by S. mutans, which contributes to biofilm formation in infective endocarditis.
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Transcriptome analysis of Streptococcus gallolyticus subsp. gallolyticus in interaction with THP-1 macrophage-like cells. PLoS One 2017; 12:e0180044. [PMID: 28672015 PMCID: PMC5495212 DOI: 10.1371/journal.pone.0180044] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Accepted: 06/08/2017] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Streptococcus gallolyticus subsp. gallolyticus (S. gallolyticus) is a pathogen of infective endocarditis. It was observed previously that this bacterium survives longer in macrophages than other species and the phagocytic uptake by and survival in THP-1 macrophages is strain-dependent. METHODS The phagocytosis assay was performed with THP-1 macrophages. S. gallolyticus specific whole genome microarrays were used for transcriptome analysis. RESULTS Better survival in macrophages was observed for UCN34, BAA-2069 and ATCC43143 than for DSM16831 and LMG17956. S. gallolyticus strains show high resistance to tested bactericidal agents (acid, lysozyme and hydrogen peroxide). S. gallolyticus stimulates significant lower cytokine gene expression and causes less lysis of macrophages compared to the control strain Staphylococcus aureus. S. gallolyticus reacts to oxidative burst with a higher gene expression of NADH oxidase initially at the early phase. Expression of genes involved in D-alanylation of teichoic acid, carbohydrate metabolism and transport systems were upregulated thereafter. CONCLUSION S. gallolyticus is very resistant to bactericidal agents normally causing degradation of bacteria in phagolysosomes. Additionally, the D-alanylation of teichoic acid is an important factor for survival.
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Alves LA, Harth-Chu EN, Palma TH, Stipp RN, Mariano FS, Höfling JF, Abranches J, Mattos-Graner RO. The two-component system VicRK regulates functions associated with Streptococcus mutans resistance to complement immunity. Mol Oral Microbiol 2017; 32:419-431. [PMID: 28382721 DOI: 10.1111/omi.12183] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 03/07/2017] [Accepted: 03/29/2017] [Indexed: 12/16/2022]
Abstract
Streptococcus mutans, a dental caries pathogen, can promote systemic infections upon reaching the bloodstream. The two-component system (TCS) VicRKSm of S. mutans regulates the synthesis of and interaction with sucrose-derived exopolysaccharides (EPS), processes associated with oral and systemic virulence. In this study, we investigated the mechanisms by which VicRKSm affects S. mutans susceptibility to blood-mediated immunity. Compared with parent strain UA159, the vicKSm isogenic mutant (UAvic) showed reduced susceptibility to deposition of C3b of complement, low binding to serum immunoglobulin G (IgG), and low frequency of C3b/IgG-mediated opsonophagocytosis by polymorphonuclear cells in a sucrose-independent way (P<.05). Reverse transcriptase quantitative polymerase chain reaction analysis comparing gene expression in UA159 and UAvic revealed that genes encoding putative peptidases of the complement (pepO and smu.399) were upregulated in UAvic in the presence of serum, although genes encoding murein hydrolases (SmaA and Smu.2146c) or metabolic/surface proteins involved in bacterial interactions with host components (enolase, GAPDH) were mostly affected in a serum-independent way. Among vicKSm -downstream genes (smaA, smu.2146c, lysM, atlA, pepO, smu.399), only pepO and smu.399 were associated with UAvic phenotypes; deletion of both genes in UA159 significantly enhanced levels of C3b deposition and opsonophagocytosis (P<.05). Moreover, consistent with the fibronectin-binding function of PepO orthologues, UAvic showed increased binding to fibronectin. Reduced susceptibility to opsonophagocytosis was insufficient to enhance ex vivo persistence of UAvic in blood, which was associated with growth defects of this mutant under limited nutrient conditions. Our findings revealed that S. mutans employs mechanisms of complement evasion through peptidases, which are controlled by VicRKSm.
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Affiliation(s)
- Livia A Alves
- Department of Oral Diagnosis, Piracicaba Dental School - State University of Campinas, Piracicaba, SP, Brazil
| | - Erika N Harth-Chu
- Department of Oral Diagnosis, Piracicaba Dental School - State University of Campinas, Piracicaba, SP, Brazil
| | - Thais H Palma
- Department of Oral Diagnosis, Piracicaba Dental School - State University of Campinas, Piracicaba, SP, Brazil
| | - Rafael N Stipp
- Department of Oral Diagnosis, Piracicaba Dental School - State University of Campinas, Piracicaba, SP, Brazil
| | - Flávia S Mariano
- Department of Oral Diagnosis, Piracicaba Dental School - State University of Campinas, Piracicaba, SP, Brazil
| | - José F Höfling
- Department of Oral Diagnosis, Piracicaba Dental School - State University of Campinas, Piracicaba, SP, Brazil
| | - Jacqueline Abranches
- Department of Oral Biology, College of Dentistry - University of Florida, Gainesville, FL, USA
| | - Renata O Mattos-Graner
- Department of Oral Diagnosis, Piracicaba Dental School - State University of Campinas, Piracicaba, SP, Brazil
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Liu J, Sun L, Liu W, Guo L, Liu Z, Wei X, Ling J. A Nuclease from Streptococcus mutans Facilitates Biofilm Dispersal and Escape from Killing by Neutrophil Extracellular Traps. Front Cell Infect Microbiol 2017; 7:97. [PMID: 28401067 PMCID: PMC5368189 DOI: 10.3389/fcimb.2017.00097] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Accepted: 03/13/2017] [Indexed: 02/02/2023] Open
Abstract
Streptococcus mutans is the primary etiologic agent of dental caries and occasionally infective endocarditis, with the ability to form biofilms and disperse cells into distal sites to exacerbate and spread infection. In this study, we identified a nuclease (DeoC) as a S. mutans biofilm dispersal modulating factor through microarray analysis. In vitro assays revealed a dispersal defect of a deoC deletion mutant, and functional studies with purified protein were indicative of the biofilm dispersal activity of DeoC. Neutrophils are a key host response factor restraining bacterial spreading through the formation of neutrophil extracellular traps (NETs), which consist of a nuclear DNA backbone associated with antimicrobial peptides. Therefore, we hypothesized that the dispersed S. mutans might utilize DeoC to degrade NETs and escape killing by the immune system. It was found that S. mutans induced NET formation upon contact with neutrophils, while the presence of NETs in turn enhanced the deoC expression of S. mutans. Fluorescence microscopy inspection showed that deoC deletion resulted in a decreased NET degradation ability of S. mutans and enhanced susceptibility to neutrophil killing. Data obtained from this study assigned two important roles for DeoC in S. mutans: contributing to the spread of infection through mediating biofilm dispersal, and facilitating the escape of S. mutans from neutrophil killing through NET degradation.
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Affiliation(s)
- Jia Liu
- Guangdong Provincial Key Laboratory of Stomatology, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-Sen University Guangzhou, China
| | - Luping Sun
- Guangdong Provincial Key Laboratory of Stomatology, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-Sen University Guangzhou, China
| | - Wei Liu
- Guangdong Provincial Key Laboratory of Stomatology, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-Sen University Guangzhou, China
| | - Lihong Guo
- Guangdong Provincial Key Laboratory of Stomatology, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-Sen University Guangzhou, China
| | - Zhaohui Liu
- Guangdong Provincial Key Laboratory of Stomatology, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-Sen University Guangzhou, China
| | - Xi Wei
- Guangdong Provincial Key Laboratory of Stomatology, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-Sen University Guangzhou, China
| | - Junqi Ling
- Guangdong Provincial Key Laboratory of Stomatology, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-Sen University Guangzhou, China
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Pinkston KL, Gao P, Singh KV, Azhdarinia A, Murray BE, Sevick-Muraca EM, Harvey BR. Antibody Guided Molecular Imaging of Infective Endocarditis. Methods Mol Biol 2017; 1535:229-241. [PMID: 27914083 DOI: 10.1007/978-1-4939-6673-8_15] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
In this protocol, we describe the application of using a high affinity monoclonal antibody generated against the major pilin protein component of the pilin structure of Enterococcus faecalis as a PET imaging agent for enterococcal endocarditis detection. The anti-pilin -mAb 64Cu conjugate was able to specifically label enterococcal endocarditis vegetation in vivo in a rodent endocarditis model. By targeting pili, a covalently linked surface antigen extending from the bacterial surface, we provided evidence that gram-positive pilin represent a logical surface antigen to define or target an infectious agent for molecularly guided imaging. Our goal in providing a detailed protocol of our efforts is to enable others to build upon this methodology to answer pertinent translational and basic research questions in the pursuit of diagnosis and treatment of infective endocarditis.
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Affiliation(s)
- Kenneth L Pinkston
- Center for Molecular Imaging, Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases, The University of Texas Health Science Center at Houston, 1825 Pressler St., Houston, TX, 77030, USA
| | - Peng Gao
- Center for Molecular Imaging, Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases, The University of Texas Health Science Center at Houston, 1825 Pressler St., Houston, TX, 77030, USA
| | - Kavindra V Singh
- Division of Infectious Diseases, Department of Internal Medicine, The University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Ali Azhdarinia
- Center for Molecular Imaging, Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases, The University of Texas Health Science Center at Houston, 1825 Pressler St., Houston, TX, 77030, USA
| | - Barbara E Murray
- Division of Infectious Diseases, Department of Internal Medicine, The University of Texas Health Science Center at Houston, Houston, TX, USA
- Department of Microbiology and Molecular Genetics, The University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Eva M Sevick-Muraca
- Center for Molecular Imaging, Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases, The University of Texas Health Science Center at Houston, 1825 Pressler St., Houston, TX, 77030, USA
| | - Barrett R Harvey
- Center for Molecular Imaging, Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases, The University of Texas Health Science Center at Houston, 1825 Pressler St., Houston, TX, 77030, USA.
- Division of Infectious Diseases, Department of Internal Medicine, The University of Texas Health Science Center at Houston, Houston, TX, USA.
- Department of Microbiology and Molecular Genetics, The University of Texas Health Science Center at Houston, Houston, TX, USA.
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Understanding the Streptococcus mutans Cid/Lrg System through CidB Function. Appl Environ Microbiol 2016; 82:6189-6203. [PMID: 27520814 DOI: 10.1128/aem.01499-16] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Accepted: 08/05/2016] [Indexed: 01/09/2023] Open
Abstract
The Streptococcus mutans lrgAB and cidAB operons have been previously described as a potential model system to dissect the complexity of biofilm development and virulence of S. mutans Herein, we have attempted to further characterize the Cid/Lrg system by focusing on CidB, which has been shown to be critical for the ability of S. mutans to survive and persist in a nonpreferred oxygen-enriched condition. We have found that the expression level of cidB is critical to oxidative stress tolerance of S. mutans, most likely by impacting lrg expression. Intriguingly, the impaired aerobic growth phenotype of the cidB mutant could be restored by the additional loss of either CidA or LrgA. Growth-dependent expression of cid and lrg was demonstrated to be tightly under the control of both CcpA and the VicKR two-component system (TCS), regulators known to play an essential role in controlling major catabolic pathways and cell envelope homeostasis, respectively. RNA sequencing (RNA-Seq) analysis revealed that mutation of cidB resulted in global gene expression changes, comprising major domains of central metabolism and virulence processes, particularly in those involved with oxidative stress resistance. Loss of CidB also significantly changed the expression of genes related to genomic islands (GI) TnSmu1 and TnSmu2, the CRISPR (clustered regularly interspaced short palindromic repeats)-Cas system, and toxin-antitoxin (T/A) modules. Taken together, these data show that CidB impinges on the stress response, as well as the fundamental cellular physiology of S. mutans, and further suggest a potential link between Cid/Lrg-mediated cellular processes, S. mutans pathogenicity, and possible programmed growth arrest and cell death mechanisms. IMPORTANCE The ability of Streptococcus mutans to survive a variety of harmful or stressful conditions and to emerge as a numerically significant member of stable oral biofilm communities are essential elements for its persistence and cariogenicity. In this study, the homologous cidAB and lrgAB operons, previously identified as being highly balanced and coordinated during S. mutans aerobic growth, were further characterized through the functional and transcriptomic analysis of CidB. Precise control of CidB levels is shown to impact the expression of lrg, oxidative stress tolerance, major metabolic domains, and the molecular modules linked to cell death and lysis. This study advances our understanding of the Cid/Lrg system as a key player in the integration of complex environmental signals (such as oxidative stress) into the regulatory networks that modulate S. mutans virulence and cell homeostasis.
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Hwang G, Liu Y, Kim D, Sun V, Aviles-Reyes A, Kajfasz JK, Lemos JA, Koo H. Simultaneous spatiotemporal mapping of in situ pH and bacterial activity within an intact 3D microcolony structure. Sci Rep 2016; 6:32841. [PMID: 27604325 PMCID: PMC5015094 DOI: 10.1038/srep32841] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Accepted: 08/15/2016] [Indexed: 02/07/2023] Open
Abstract
Biofilms are comprised of bacterial-clusters (microcolonies) enmeshed in an extracellular matrix. Streptococcus mutans can produce exopolysaccharides (EPS)-matrix and assemble microcolonies with acidic microenvironments that can cause tooth-decay despite the surrounding neutral-pH found in oral cavity. How the matrix influences the pH and bacterial activity locally remains unclear. Here, we simultaneously analyzed in situ pH and gene expression within intact biofilms and measured the impact of damage to the surrounding EPS-matrix. The spatiotemporal changes of these properties were characterized at a single-microcolony level following incubation in neutral-pH buffer. The middle and bottom-regions as well as inner-section within the microcolony 3D structure were resistant to neutralization (vs. upper and peripheral-region), forming an acidic core. Concomitantly, we used a green fluorescent protein (GFP) reporter to monitor expression of the pH-responsive atpB (PatpB::gfp) by S. mutans within microcolonies. The atpB expression was induced in the acidic core, but sharply decreased at peripheral/upper microcolony regions, congruent with local pH microenvironment. Enzymatic digestion of the surrounding matrix resulted in nearly complete neutralization of microcolony interior and down-regulation of atpB. Altogether, our data reveal that biofilm matrix facilitates formation of an acidic core within microcolonies which in turn activates S. mutans acid-stress response, mediating both the local environment and bacterial activity in situ.
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Affiliation(s)
- Geelsu Hwang
- Biofilm Research Labs, Levy Center for Oral Health, Department of Orthodontics and Divisions of Pediatric Dentistry &Community Oral Health, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Yuan Liu
- Biofilm Research Labs, Levy Center for Oral Health, Department of Orthodontics and Divisions of Pediatric Dentistry &Community Oral Health, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Dongyeop Kim
- Biofilm Research Labs, Levy Center for Oral Health, Department of Orthodontics and Divisions of Pediatric Dentistry &Community Oral Health, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Victor Sun
- Biofilm Research Labs, Levy Center for Oral Health, Department of Orthodontics and Divisions of Pediatric Dentistry &Community Oral Health, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Alejandro Aviles-Reyes
- Department of Oral Biology, University of Florida College of Dentistry, Gainesville, FL, USA
| | - Jessica K Kajfasz
- Department of Oral Biology, University of Florida College of Dentistry, Gainesville, FL, USA
| | - Jose A Lemos
- Department of Oral Biology, University of Florida College of Dentistry, Gainesville, FL, USA
| | - Hyun Koo
- Biofilm Research Labs, Levy Center for Oral Health, Department of Orthodontics and Divisions of Pediatric Dentistry &Community Oral Health, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
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Oliveira FAF, Forte CPF, Silva PGDB, Lopes CB, Montenegro RC, Santos ÂKCRD, Sobrinho CRMR, Mota MRL, Sousa FB, Alves APNN. Molecular Analysis of Oral Bacteria in Heart Valve of Patients With Cardiovascular Disease by Real-Time Polymerase Chain Reaction. Medicine (Baltimore) 2015; 94:e2067. [PMID: 26632711 PMCID: PMC5058980 DOI: 10.1097/md.0000000000002067] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Revised: 10/16/2015] [Accepted: 10/23/2015] [Indexed: 11/25/2022] Open
Abstract
Structural deficiencies and functional abnormalities of heart valves represent an important cause of cardiovascular morbidity and mortality, and a number of diseases, such as aortic stenosis, have been recently associated with infectious agents. This study aimed to analyze oral bacteria in dental plaque, saliva, and cardiac valves of patients with cardiovascular disease. Samples of supragingival plaque, subgingival plaque, saliva, and cardiac valve tissue were collected from 42 patients with heart valve disease. Molecular analysis of Streptococcus mutans, Prevotella intermedia, Porphyromonas gingivalis, and Treponema denticola was performed through real-time PCR. The micro-organism most frequently detected in heart valve samples was the S. mutans (89.3%), followed by P. intermedia (19.1%), P. gingivalis (4.2%), and T. denticola (2.1%). The mean decayed, missing, filled teeth (DMFT) was 26.4 ± 6.9 (mean ± SD), and according to the highest score of periodontal disease observed for each patient, periodontal pockets > 4 mm and dental calculus were detected in 43.4% and 34.7% of patients, respectively. In conclusion, oral bacteria, especially S. mutans, were found in the cardiac valve samples of patients with a high rate of caries and gingivitis/periodontitis.
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Affiliation(s)
- Francisco Artur Forte Oliveira
- From the Department of Stomatology and Oral Pathology, School of Dentistry, Federal University of Ceara, Fortaleza, Ceará (FAFO, CPF, PGBS, MRLM, FBS); Department of Oral Pathology, School of Dentistry, Federal University of Ceara, Fortaleza, Ceará (APNNA); Department of Clinical Medicine, School of Medicine, Federal University of Ceara, Fortaleza, Ceará (CRMRS); Laboratory of Human and Medical Genetics, Institute of Biological Sciences, Federal University of Pará, Belém, Pará, Brazil (CBL, AKCRS); Human Cytogenetics Laboratory, Institute of Biological Sciences, Federal University of Pará, Belém, Pará, Brazil (RCM)
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Activated human valvular interstitial cells sustain interleukin-17 production to recruit neutrophils in infective endocarditis. Infect Immun 2015; 83:2202-12. [PMID: 25776751 DOI: 10.1128/iai.02965-14] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Accepted: 03/05/2015] [Indexed: 12/07/2022] Open
Abstract
The mechanisms that underlie valvular inflammation in streptococcus-induced infective endocarditis (IE) remain unclear. We previously demonstrated that streptococcal glucosyltransferases (GTFs) can activate human heart valvular interstitial cells (VIC) to secrete interleukin-6 (IL-6), a cytokine involved in T helper 17 (Th17) cell differentiation. Here, we tested the hypothesis that activated VIC can enhance neutrophil infiltration through sustained IL-17 production, leading to valvular damage. To monitor cytokine and chemokine production, leukocyte recruitment, and the induction or expansion of CD4(+) CD45RA(-) CD25(-) CCR6(+) Th17 cells, primary human VIC were cultured in vitro and activated by GTFs. Serum cytokine levels were measured using an enzyme-linked immunosorbent assay (ELISA), and neutrophils and Th17 cells were detected by immunohistochemistry in infected valves from patients with IE. The expression of IL-21, IL-23, IL-17, and retinoic acid receptor-related orphan receptor C (Rorc) was upregulated in GTF-activated VIC, which may enhance the proliferation of memory Th17 cells in an IL-6-dependent manner. Many chemokines, including chemokine (C-X-C motif) ligand 1 (CXCL1), were upregulated in GTF-activated VIC, which might recruit neutrophils and CD4(+) T cells. Moreover, CXCL1 production in VIC was induced in a dose-dependent manner by IL-17 to enhance neutrophil chemotaxis. CXCL1-expressing VIC and infiltrating neutrophils could be detected in infected valves, and serum concentrations of IL-17, IL-21, and IL-23 were increased in patients with IE compared to healthy donors. Furthermore, elevated serum IL-21 levels have been significantly associated with severe valvular damage, including rupture of chordae tendineae, in IE patients. Our findings suggest that VIC are activated by bacterial modulins to recruit neutrophils and that such activities might be further enhanced by the production of Th17-associated cytokines. Together, these factors can amplify the release of neutrophilic contents in situ, which might lead to severe valvular damage.
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Jung CJ, Yeh CY, Hsu RB, Lee CM, Shun CT, Chia JS. Endocarditis pathogen promotes vegetation formation by inducing intravascular neutrophil extracellular traps through activated platelets. Circulation 2014; 131:571-81. [PMID: 25527699 DOI: 10.1161/circulationaha.114.011432] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
BACKGROUND Endocarditis-inducing streptococci form multilayered biofilms in complex with aggregated platelets on injured heart valves, but the host factors that interconnect and entrap these bacteria-platelet aggregates to promote vegetation formation were unclear. METHODS AND RESULTS In a Streptococcus mutans endocarditis rat model, we identified layers of neutrophil extracellular traps interconnecting and entrapping bacteria-platelet aggregates inside vegetation that could be reduced significantly in size along with diminished colonizing bacteria by prophylaxis with intravascular DNase I alone. The combination of activated platelets and specific immunoglobulin G-adsorbed bacteria are required to induce the formation of neutrophil extracellular traps through multiple activation pathways. Bacteria play key roles in coordinating the signaling through spleen tyrosine kinase, Src family kinases, phosphatidylinositol-3-kinase, and p38 mitogen-activated protein kinase pathways to upregulate the expression of P-selectin in platelets, while inducing reactive oxygen species-dependent citrullination in the arm of neutrophils. Neutrophil extracellular traps in turn serve as the scaffold to further enhance and entrap bacteria-platelet aggregate formation and expansion. CONCLUSIONS Neutrophil extracellular traps promote and expand vegetation formation through enhancing and entrapping bacteria-platelet aggregates on the injured heart valves.
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Affiliation(s)
- Chiau-Jing Jung
- From the Graduate Institute of Microbiology, College of Medicine, National Taiwan University, Taipei, Taiwan (C.-J.J., J.-S.C.); Graduate Institute of Immunology, College of Medicine, National Taiwan University, Taipei, Taiwan (C.-Y.Y., J.-S.C.); Department of Surgery, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan (R.-B.H.); Department of Internal Medicine, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan (C.-M.L.); and Department of Forensic Medicine, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan (C.-T.S.)
| | - Chiou-Yueh Yeh
- From the Graduate Institute of Microbiology, College of Medicine, National Taiwan University, Taipei, Taiwan (C.-J.J., J.-S.C.); Graduate Institute of Immunology, College of Medicine, National Taiwan University, Taipei, Taiwan (C.-Y.Y., J.-S.C.); Department of Surgery, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan (R.-B.H.); Department of Internal Medicine, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan (C.-M.L.); and Department of Forensic Medicine, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan (C.-T.S.)
| | - Ron-Bin Hsu
- From the Graduate Institute of Microbiology, College of Medicine, National Taiwan University, Taipei, Taiwan (C.-J.J., J.-S.C.); Graduate Institute of Immunology, College of Medicine, National Taiwan University, Taipei, Taiwan (C.-Y.Y., J.-S.C.); Department of Surgery, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan (R.-B.H.); Department of Internal Medicine, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan (C.-M.L.); and Department of Forensic Medicine, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan (C.-T.S.)
| | - Chii-Ming Lee
- From the Graduate Institute of Microbiology, College of Medicine, National Taiwan University, Taipei, Taiwan (C.-J.J., J.-S.C.); Graduate Institute of Immunology, College of Medicine, National Taiwan University, Taipei, Taiwan (C.-Y.Y., J.-S.C.); Department of Surgery, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan (R.-B.H.); Department of Internal Medicine, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan (C.-M.L.); and Department of Forensic Medicine, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan (C.-T.S.)
| | - Chia-Tung Shun
- From the Graduate Institute of Microbiology, College of Medicine, National Taiwan University, Taipei, Taiwan (C.-J.J., J.-S.C.); Graduate Institute of Immunology, College of Medicine, National Taiwan University, Taipei, Taiwan (C.-Y.Y., J.-S.C.); Department of Surgery, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan (R.-B.H.); Department of Internal Medicine, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan (C.-M.L.); and Department of Forensic Medicine, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan (C.-T.S.)
| | - Jean-San Chia
- From the Graduate Institute of Microbiology, College of Medicine, National Taiwan University, Taipei, Taiwan (C.-J.J., J.-S.C.); Graduate Institute of Immunology, College of Medicine, National Taiwan University, Taipei, Taiwan (C.-Y.Y., J.-S.C.); Department of Surgery, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan (R.-B.H.); Department of Internal Medicine, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan (C.-M.L.); and Department of Forensic Medicine, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan (C.-T.S.).
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Contribution of the interaction of Streptococcus mutans serotype k strains with fibrinogen to the pathogenicity of infective endocarditis. Infect Immun 2014; 82:5223-34. [PMID: 25287921 DOI: 10.1128/iai.02164-14] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Streptococcus mutans, a pathogen responsible for dental caries, is occasionally isolated from the blood of patients with bacteremia and infective endocarditis (IE). Our previous study demonstrated that serotype k-specific bacterial DNA is frequently detected in S. mutans-positive heart valve specimens extirpated from IE patients. However, the reason for this frequent detection remains unknown. In the present study, we analyzed the virulence of IE from S. mutans strains, focusing on the characterization of serotype k strains, most of which are positive for the 120-kDa cell surface collagen-binding protein Cbm and negative for the 190-kDa protein antigen (PA) known as SpaP, P1, antigen I/II, and other designations. Fibrinogen-binding assays were performed with 85 clinical strains classified by Cbm and PA expression levels. The Cbm(+)/PA(-) group strains had significantly higher fibrinogen-binding rates than the other groups. Analysis of platelet aggregation revealed that SA31, a Cbm(+)/PA(-) strain, induced an increased level of aggregation in the presence of fibrinogen, while negligible aggregation was induced by the Cbm-defective isogenic mutant SA31CBD. A rat IE model with an artificial impairment of the aortic valve created using a catheter showed that extirpated heart valves in the SA31 group displayed a prominent vegetation mass not seen in those in the SA31CBD group. These findings could explain why Cbm(+)/PA(-) strains are highly virulent and are related to the development of IE, and the findings could also explain the frequent detection of serotype k DNA in S. mutans-positive heart valve clinical specimens.
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Papadimitriou K, Anastasiou R, Mavrogonatou E, Blom J, Papandreou NC, Hamodrakas SJ, Ferreira S, Renault P, Supply P, Pot B, Tsakalidou E. Comparative genomics of the dairy isolate Streptococcus macedonicus ACA-DC 198 against related members of the Streptococcus bovis/Streptococcus equinus complex. BMC Genomics 2014; 15:272. [PMID: 24713045 PMCID: PMC4051162 DOI: 10.1186/1471-2164-15-272] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2013] [Accepted: 04/01/2014] [Indexed: 12/21/2022] Open
Abstract
Background Within the genus Streptococcus, only Streptococcus
thermophilus is used as a starter culture in food fermentations.
Streptococcus macedonicus though, which belongs to the
Streptococcus bovis/Streptococcus equinus complex
(SBSEC), is also frequently isolated from fermented foods mainly of dairy
origin. Members of the SBSEC have been implicated in human endocarditis and
colon cancer. Here we compare the genome sequence of the dairy isolate
S. macedonicus ACA-DC 198 to the other SBSEC genomes in order
to assess in silico its potential adaptation to milk and its
pathogenicity status. Results Despite the fact that the SBSEC species were found tightly related based on
whole genome phylogeny of streptococci, two distinct patterns of evolution
were identified among them. Streptococcus macedonicus, Streptococcus
infantarius CJ18 and Streptococcus pasteurianus ATCC 43144
seem to have undergone reductive evolution resulting in significantly
diminished genome sizes and increased percentages of potential pseudogenes
when compared to Streptococcus gallolyticus subsp.
gallolyticus. In addition, the three species seem to have lost
genes for catabolizing complex plant carbohydrates and for detoxifying toxic
substances previously linked to the ability of S. gallolyticus to
survive in the rumen. Analysis of the S. macedonicus genome
revealed features that could support adaptation to milk, including an extra
gene cluster for lactose and galactose metabolism, a proteolytic system for
casein hydrolysis, auxotrophy for several vitamins, an increased ability to
resist bacteriophages and horizontal gene transfer events with the dairy
Lactococcus lactis and S. thermophilus as potential
donors. In addition, S. macedonicus lacks several
pathogenicity-related genes found in S. gallolyticus. For example,
S. macedonicus has retained only one (i.e. the pil3)
of the three pilus gene clusters which may mediate the binding of S.
gallolyticus to the extracellular matrix. Unexpectedly, similar
findings were obtained not only for the dairy S. infantarius CJ18,
but also for the blood isolate S. pasteurianus ATCC 43144. Conclusions Our whole genome analyses suggest traits of adaptation of S.
macedonicus to the nutrient-rich dairy environment. During this
process the bacterium gained genes presumably important for this new
ecological niche. Finally, S. macedonicus carries a reduced number
of putative SBSEC virulence factors, which suggests a diminished pathogenic
potential.
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Affiliation(s)
- Konstantinos Papadimitriou
- Laboratory of Dairy Research, Department of Food Science and Human Nutrition, Agricultural University of Athens, Iera Odos 75, Athens 118 55, Greece.
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Krzyściak W, Jurczak A, Kościelniak D, Bystrowska B, Skalniak A. The virulence of Streptococcus mutans and the ability to form biofilms. Eur J Clin Microbiol Infect Dis 2014; 33:499-515. [PMID: 24154653 PMCID: PMC3953549 DOI: 10.1007/s10096-013-1993-7] [Citation(s) in RCA: 342] [Impact Index Per Article: 34.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2013] [Accepted: 10/02/2013] [Indexed: 01/01/2023]
Abstract
In some diseases, a very important role is played by the ability of bacteria to form multi-dimensional complex structure known as biofilm. The most common disease of the oral cavity, known as dental caries, is a top leader. Streptococcus mutans, one of the many etiological factors of dental caries, is a microorganism which is able to acquire new properties allowing for the expression of pathogenicity determinants determining its virulence in specific environmental conditions. Through the mechanism of adhesion to a solid surface, S. mutans is capable of colonizing the oral cavity and also of forming bacterial biofilm. Additional properties enabling S. mutans to colonize the oral cavity include the ability to survive in an acidic environment and specific interaction with other microorganisms colonizing this ecosystem. This review is an attempt to establish which characteristics associated with biofilm formation--virulence determinants of S. mutans--are responsible for the development of dental caries. In order to extend the knowledge of the nature of Streptococcus infections, an attempt to face the following problems will be made: Biofilm formation as a complex process of protein-bacterium interaction. To what extent do microorganisms of the cariogenic flora exemplified by S. mutans differ in virulence determinants "expression" from microorganisms of physiological flora? How does the environment of the oral cavity and its microorganisms affect the biofilm formation of dominant species? How do selected inhibitors affect the biofilm formation of cariogenic microorganisms?
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Affiliation(s)
- W Krzyściak
- Department of Medical Diagnostics, Faculty of Pharmacy, Medical College, Jagiellonian University, UJCM 9 Medyczna St., 30-688, Krakow, Poland,
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Bedran TBL, Grignon L, Spolidorio DP, Grenier D. Subinhibitory concentrations of triclosan promote Streptococcus mutans biofilm formation and adherence to oral epithelial cells. PLoS One 2014; 9:e89059. [PMID: 24551218 PMCID: PMC3923858 DOI: 10.1371/journal.pone.0089059] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Accepted: 01/13/2014] [Indexed: 01/05/2023] Open
Abstract
Triclosan is a general membrane-active agent with a broad-spectrum antimicrobial activity that is commonly used in oral care products. In this study, we investigated the effect of sub-minimum inhibitory concentrations (MICs) of triclosan on the capacity of the cariogenic bacterium Streptococcus mutans to form biofilm and adhere to oral epithelial cells. As quantified by crystal violet staining, biofilm formation by two reference strains of S. mutans was dose-dependently promoted, in the range of 2.2- to 6.2-fold, by 1/2 and 1/4 MIC of triclosan. Observations by scanning electron microscopy revealed the presence of a dense biofilm attached to the polystyrene surface. Growth of S. mutans in the presence of triclosan at sub-MICs also increased its capacity to adhere to a monolayer of gingival epithelial cells. The expression of several genes involved in adherence and biofilm formation in S. mutans was investigated by quantitative RT-PCR. It was found that sub-MICs of triclosan significantly increased the expression of comD, gtfC, and luxS, and to a lesser extent of gtfB and atlA genes. These findings stress the importance of maintaining effective bactericidal concentrations of therapeutic triclosan since sub-MICs may promote colonization of the oral cavity by S. mutans.
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Affiliation(s)
- Telma Blanca Lombardo Bedran
- Department of Oral Diagnosis and Surgery, Araraquara Dental School, State University of São Paulo, São Paulo, Brazil
| | - Louis Grignon
- Oral Ecology Research Group, Faculty of Dentistry, Université Laval, Quebec City, Quebec, Canada
| | - Denise Palomari Spolidorio
- Department of Physiology and Pathology, Araraquara Dental School, State University of São Paulo, São Paulo, Brazil
| | - Daniel Grenier
- Oral Ecology Research Group, Faculty of Dentistry, Université Laval, Quebec City, Quebec, Canada
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Putonti C, Nowicki B, Shaffer M, Fofanov Y, Nowicki S. Where does Neisseria acquire foreign DNA from: an examination of the source of genomic and pathogenic islands and the evolution of the Neisseria genus. BMC Evol Biol 2013; 13:184. [PMID: 24007216 PMCID: PMC3848584 DOI: 10.1186/1471-2148-13-184] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2013] [Accepted: 08/28/2013] [Indexed: 02/03/2023] Open
Abstract
Background Pathogenicity islands (PAIs) or genomic islands (GEIs) are considered to be the result of a recent horizontal transfer. Detecting PAIs/GEIs as well as their putative source can provide insight into the organism’s pathogenicity within its host. Previously we introduced a tool called S-plot which provides a visual representation of the variation in compositional properties across and between genomic sequences. Utilizing S-plot and new functionality developed here, we examined 18 publicly available Neisseria genomes, including strains of both pathogenic and non-pathogenic species, in order to identify regions of unusual compositional properties (RUCPs) using both a sliding window as well as a gene-by-gene approach. Results Numerous GEIs and PAIs were identified including virulence genes previously found within the pathogenic Neisseria species. While some genes were conserved amongst all species, only pathogenic species, or an individual species, a number of genes were detected that are unique to an individual strain. While the majority of such genes have an origin unknown, a number of putative sources including pathogenic and capsule-containing bacteria were determined, indicative of gene exchange between Neisseria spp. and other bacteria within their microhabitat. Furthermore, we uncovered evidence that both N. meningitidis and N. gonorrhoeae have separately acquired DNA from their human host. Data suggests that all three Neisseria species have received horizontally transferred elements post-speciation. Conclusions Using this approach, we were able to not only find previously identified regions of virulence but also new regions which may be contributing to the virulence of the species. This comparative analysis provides a means for tracing the evolutionary history of the acquisition of foreign DNA within this genus. Looking specifically at the RUCPs present within the 18 genomes considered, a stronger similarity between N. meningitidis and N. lactamica is observed, suggesting that N. meningitidis arose before N. gonorrhoeae.
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Affiliation(s)
- Catherine Putonti
- Department of Biology, Loyola University Chicago, 1032 W, Sheridan Rd, Chicago, IL 60660, USA.
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Krzyściak W, Pluskwa KK, Jurczak A, Kościelniak D. The pathogenicity of the Streptococcus genus. Eur J Clin Microbiol Infect Dis 2013; 32:1361-76. [PMID: 24141975 PMCID: PMC3824240 DOI: 10.1007/s10096-013-1914-9] [Citation(s) in RCA: 82] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2013] [Accepted: 06/11/2013] [Indexed: 12/11/2022]
Abstract
Streptococcus infections are still one of the important problems facing contemporary medicine. As the World Health Organization (WHO) warns, Streptococcus pneumoniae is responsible for the highest number of pneumonia cases all over the world. Despite an increasing number of pneumococcal vaccinations, incidences of disease connected to this pathogen's infection stay at the same level, which is related to a constantly increasing number of infections caused by nonvaccinal serotypes. Unfortunately, the pathogenicity of bacteria of the Streptococcus genus is also connected to species considered to be physiological flora in humans or animals and, additionally, new species exhibiting pathogenic potential have been discovered. This paper presents an opinion concerning the epidemiology of streptococci infections based on case studies and other publications devoted to this problem. It also sheds new light based on recent reports on the prevention of protective vaccinations application in the case of streptococci infections.
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Affiliation(s)
- W Krzyściak
- Department of Medical Diagnostics, Pharmacy Faculty, Jagiellonian University Medical College, 9 Medyczna St., 30-688, Krakow, Poland,
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Streptococcus tigurinus is highly virulent in a rat model of experimental endocarditis. Int J Med Microbiol 2013; 303:498-504. [PMID: 23856340 DOI: 10.1016/j.ijmm.2013.06.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Revised: 05/14/2013] [Accepted: 06/16/2013] [Indexed: 01/15/2023] Open
Abstract
Streptococcus tigurinus is responsible for systemic infections in humans including infective endocarditis. We investigated whether the invasive trait of S. tigurinus in humans correlated with an increased ability to induce IE in rats. Rats with catheter-induced aortic vegetations were inoculated with 10⁴ CFU/ml of either of four S. tigurinus strains AZ_3a(T), AZ_4a, AZ_8 and AZ_14, isolated from patients with infective endocarditis or with the well known IE pathogen Streptococcus gordonii (Challis). Aortic infection was assessed after 24 h. S. tigurinus AZ_3a(T), AZ_4a and AZ_14 produced endocarditis in ≥80% of rats whereas S. gordonii produced endocarditis in only 33% of animals (P<0.05). S. tigurinus AZ_8 caused vegetation infection in 56% of the animals. The capacity of S. tigurinus to induce aortic infection was not related to their ability to bind extracellular matrix proteins (fibrinogen, fibronectin or collagen) or to trigger platelet aggregation. However, all S. tigurinus isolates showed an enhanced resistance to phagocytosis by macrophages and two of them had an increased ability to enter endothelial cells, key attributes of invasive streptococcal species.
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Lapirattanakul J, Nomura R, Nemoto H, Naka S, Ooshima T, Nakano K. Multilocus sequence typing of Streptococcus mutans strains with the cbm gene encoding a novel collagen-binding protein. Arch Oral Biol 2013; 58:989-96. [PMID: 23506778 DOI: 10.1016/j.archoralbio.2013.02.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2012] [Revised: 01/29/2013] [Accepted: 02/15/2013] [Indexed: 11/25/2022]
Abstract
OBJECTIVE Streptococcus mutans, an oral pathogen associated with infective endocarditis (IE), possesses two genes encoding collagen-binding proteins, namely cnm and cbm. In this study, we used multilocus sequence typing (MLST) of S. mutans with the cbm gene. DESIGN Forty-five S. mutans strains including 15 strains with the cnm gene, 15 strains with the cbm gene, and 15 strains without these two genes were analysed by MLST. In addition, the collagen-binding properties as well as the abilities to adhere to and invade human umbilical vein endothelial cells (HUVEC) were also evaluated for all strains. RESULTS In the groups of cnm-positive and cbm-positive strains, all properties, including collagen binding, adhesion, and invasion were significantly greater than those of the cnm-cbm-negative group. Moreover, MLST revealed three clonal complexes of S. mutans possessing the cbm gene. These three clones showed no close relatedness with clones of strains containing the cnm gene. Among three clones harbouring the cbm gene, two clones belong to serotype k, and appeared to be associated with the pathogenesis of IE due to their strong collagen binding and relatively enhanced abilities to adhere to and invade endothelial cells. However, such properties were relatively weak in the other non-serotype k clone possessing the cbm gene. CONCLUSIONS MLST indicated a difference in evolution between S. mutans strains with the cbm gene and those with the cnm gene. In addition, this technique also suggested the importance of cbm-positive S. mutans clones relative to the pathogenesis of IE.
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Affiliation(s)
- Jinthana Lapirattanakul
- Department of Oral Microbiology, Faculty of Dentistry, Mahidol University, Bangkok 10400, Thailand.
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Lemos JA, Quivey RG, Koo H, Abranches J. Streptococcus mutans: a new Gram-positive paradigm? MICROBIOLOGY-SGM 2013; 159:436-445. [PMID: 23393147 DOI: 10.1099/mic.0.066134-0] [Citation(s) in RCA: 140] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Despite the enormous contributions of the bacterial paradigms Escherichia coli and Bacillus subtilis to basic and applied research, it is well known that no single organism can be a perfect representative of all other species. However, given that some bacteria are difficult, or virtually impossible, to cultivate in the laboratory, that some are recalcitrant to genetic and molecular manipulation, and that others can be extremely dangerous to manipulate, the use of model organisms will continue to play an important role in the development of basic research. In particular, model organisms are very useful for providing a better understanding of the biology of closely related species. Here, we discuss how the lifestyle, the availability of suitable in vitro and in vivo systems, and a thorough understanding of the genetics, biochemistry and physiology of the dental pathogen Streptococcus mutans have greatly advanced our understanding of important areas in the field of bacteriology such as interspecies biofilms, competence development and stress responses. In this article, we provide an argument that places S. mutans, an organism that evolved in close association with the human host, as a novel Gram-positive model organism.
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Affiliation(s)
- José A Lemos
- Center for Oral Biology and Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, NY 14642, USA
| | - Robert G Quivey
- Center for Oral Biology and Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, NY 14642, USA
| | - Hyun Koo
- Center for Oral Biology and Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, NY 14642, USA
| | - Jacqueline Abranches
- Center for Oral Biology and Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, NY 14642, USA
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Wichgers Schreur PJ, van Weeghel C, Rebel JMJ, Smits MA, van Putten JPM, Smith HE. Lysozyme resistance in Streptococcus suis is highly variable and multifactorial. PLoS One 2012; 7:e36281. [PMID: 22558419 PMCID: PMC3340348 DOI: 10.1371/journal.pone.0036281] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2011] [Accepted: 04/04/2012] [Indexed: 12/19/2022] Open
Abstract
Background Streptococcus suis is an important infectious agent for pigs and occasionally for humans. The host innate immune system plays a key role in preventing and eliminating S. suis infections. One important constituent of the innate immune system is the protein lysozyme, which is present in a variety of body fluids and immune cells. Lysozyme acts as a peptidoglycan degrading enzyme causing bacterial lysis. Several pathogens have developed mechanisms to evade lysozyme-mediated killing. In the present study we compared the lysozyme sensitivity of various S. suis isolates and investigated the molecular basis of lysozyme resistance for this pathogen. Results The lysozyme minimal inhibitory concentrations of a wide panel of S. suis isolates varied between 0.3 to 10 mg/ml. By inactivating the oatA gene in a serotype 2 and a serotype 9 strain, we showed that OatA-mediated peptidoglycan modification partly contributes to lysozyme resistance. Furthermore, inactivation of the murMN operon provided evidence that additional peptidoglycan crosslinking is not involved in lysozyme resistance in S. suis. Besides a targeted approach, we also used an unbiased approach for identifying factors involved in lysozyme resistance. Based on whole genome comparisons of a lysozyme sensitive strain and selected lysozyme resistant derivatives, we detected several single nucleotide polymorphisms (SNPs) that were correlated with the lysozyme resistance trait. Two SNPs caused defects in protein expression of an autolysin and a capsule sugar transferase. Analysis of specific isogenic mutants, confirmed the involvement of autolysin activity and capsule structures in lysozyme resistance of S. suis. Conclusions This study shows that lysozyme resistance levels are highly variable among S. suis isolates and serotypes. Furthermore, the results show that lysozyme resistance in S. suis can involve different mechanisms including OatA-mediated peptidolycan modification, autolysin activity and capsule production.
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Affiliation(s)
- Paul J. Wichgers Schreur
- Central Veterinary Institute, Wageningen UR, Lelystad, The Netherlands
- Department of Infectious Diseases and Immunology, Utrecht University, Utrecht, The Netherlands
| | | | | | - Mari A. Smits
- Central Veterinary Institute, Wageningen UR, Lelystad, The Netherlands
- Wageningen Livestock Research, Wageningen UR, Lelystad, The Netherlands
| | - Jos P. M. van Putten
- Department of Infectious Diseases and Immunology, Utrecht University, Utrecht, The Netherlands
| | - Hilde E. Smith
- Central Veterinary Institute, Wageningen UR, Lelystad, The Netherlands
- * E-mail:
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Jung CJ, Yeh CY, Shun CT, Hsu RB, Cheng HW, Lin CS, Chia JS. Platelets enhance biofilm formation and resistance of endocarditis-inducing streptococci on the injured heart valve. J Infect Dis 2012; 205:1066-75. [PMID: 22357661 DOI: 10.1093/infdis/jis021] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Infective endocarditis is a typical biofilm-associated infectious disease frequently caused by commensal streptococci, but the contribution of host factors in biofilm formation is unclear. We found that platelets are essential for in vitro biofilm formation by Streptococcus mutans or Streptococcus gordonii grown in human plasma. The biofilms were composed of bacterial floes embedded with platelet aggregates in layers, and a similar architecture was also detected in situ on the injured valves of a rat model of experimental endocarditis. Similar to planktonic cells, the streptococci in biofilms were also able to induce platelet aggregation, which facilitates multilayer biofilm formation. Entrapping of platelets directly enhances the resistance of streptococcal biofilms to clindamycin. Prophylactic antibiotics or aspirin can reduce but not prevent or abolish biofilm formation on injured heart valves. Therefore, the platelet is a host factor for commensal streptococci in the circulation to consolidate biofilm formation and protect bacteria against antibiotics.
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Affiliation(s)
- Chiau-Jing Jung
- Graduate Institute of Microbiology, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan, ROC
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Negrini TC, Duque C, Vizoto NL, Stipp RN, Mariano FS, Höfling JF, Graner E, Mattos-Graner RO. Influence of VicRK and CovR on the interactions of Streptococcus mutans with phagocytes. Oral Dis 2012; 18:485-93. [DOI: 10.1111/j.1601-0825.2011.01896.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Characterization and functional analysis of atl, a novel gene encoding autolysin in Streptococcus suis. J Bacteriol 2012; 194:1464-73. [PMID: 22228730 DOI: 10.1128/jb.06231-11] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Streptococcus suis serotype 2 (S. suis 2) is an important swine and human pathogen responsible for septicemia and meningitis. A novel gene, designated atl and encoding a major autolysin of S. suis 2 virulent strain HA9801, was identified and characterized in this study. The Atl protein contains 1,025 amino acids with a predicted molecular mass of 113 kDa and has a conserved N-acetylmuramoyl-l-alanine amidase domain. Recombinant Atl was expressed in Escherichia coli, and its bacteriolytic and fibronectin-binding activities were confirmed by zymography and Western affinity blotting. Two bacteriolytic bands were shown in the sodium dodecyl sulfate extracts of HA9801, while both were absent from the atl inactivated mutant. Cell chains of the mutant strain became longer than that of the parental strain. In the autolysis assay, HA9801 decreased to 20% of the initial optical density (OD) value, while the mutant strain had almost no autolytic activity. The biofilm capacity of the atl mutant was reduced ∼30% compared to the parental strain. In the zebrafish infection model, the 50% lethal dose of the mutant strain was increased up to 5-fold. Furthermore, the adherence to HEp-2 cells of the atl mutant was 50% less than that of the parental strain. Based on the functional analysis of the recombinant Atl and observed effects of atl inactivation on HA9801, we conclude that Atl is a major autolysin of HA9801. It takes part in cell autolysis, separation of daughter cells, biofilm formation, fibronectin-binding activity, cell adhesion, and pathogenesis of HA9801.
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Uehara T, Bernhardt TG. More than just lysins: peptidoglycan hydrolases tailor the cell wall. Curr Opin Microbiol 2011; 14:698-703. [PMID: 22055466 DOI: 10.1016/j.mib.2011.10.003] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2011] [Revised: 10/08/2011] [Accepted: 10/10/2011] [Indexed: 11/15/2022]
Abstract
Enzymes that degrade the peptidoglycan (PG) cell wall layer called PG hydrolases or autolysins are often thought of as destructive forces. Phages employ them to lyse their host for the release of virion particles and some bacteria secrete them to eliminate (lyse) their competition. However, bacteria also harness the activity of PG hydrolases for important aspects of growth, division, and development. Of course, using PG hydrolases in this capacity requires that they be tightly regulated. While this has been appreciated for some time, we are only just beginning to understand the mechanisms governing the activities of these 'tailoring' enzymes. This review will focus on recent advances in this area with an emphasis on the regulation of PG hydrolases involved in cell division.
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Affiliation(s)
- Tsuyoshi Uehara
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA 02115, United States
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Bogema DR, Scott NE, Padula MP, Tacchi JL, Raymond BBA, Jenkins C, Cordwell SJ, Minion FC, Walker MJ, Djordjevic SP. Sequence TTKF ↓ QE defines the site of proteolytic cleavage in Mhp683 protein, a novel glycosaminoglycan and cilium adhesin of Mycoplasma hyopneumoniae. J Biol Chem 2011; 286:41217-41229. [PMID: 21969369 DOI: 10.1074/jbc.m111.226084] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Mycoplasma hyopneumoniae colonizes the ciliated respiratory epithelium of swine, disrupting mucociliary function and inducing chronic inflammation. P97 and P102 family members are major surface proteins of M. hyopneumoniae and play key roles in colonizing cilia via interactions with glycosaminoglycans and mucin. The p102 paralog, mhp683, and homologs in strains from different geographic origins encode a 135-kDa pre-protein (P135) that is cleaved into three fragments identified here as P45(683), P48(683), and P50(683). A peptide sequence (TTKF↓QE) was identified surrounding both cleavage sites in Mhp683. N-terminal sequences of P48(683) and P50(683), determined by Edman degradation and mass spectrometry, confirmed cleavage after the phenylalanine residue. A similar proteolytic cleavage site was identified by mass spectrometry in another paralog of the P97/P102 family. Trypsin digestion and surface biotinylation studies showed that P45(683), P48(683), and P50(683) reside on the M. hyopneumoniae cell surface. Binding assays of recombinant proteins F1(683)-F5(683), spanning Mhp683, showed saturable and dose-dependent binding to biotinylated heparin that was inhibited by unlabeled heparin, fucoidan, and mucin. F1(683)-F5(683) also bound porcine epithelial cilia, and antisera to F2(683) and F5(683) significantly inhibited cilium binding by M. hyopneumoniae cells. These data suggest that P45(683), P48(683), and P50(683) each display cilium- and proteoglycan-binding sites. Mhp683 is the first characterized glycosaminoglycan-binding member of the P102 family.
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Affiliation(s)
- Daniel R Bogema
- NSW Department of Primary Industries, Elizabeth Macarthur Agricultural Institute, Camden 2567, New South Wales, Australia; School of Biological Sciences, University of Wollongong, Wollongong 2522, New South Wales, Australia
| | - Nichollas E Scott
- School of Molecular and Microbial Biosciences, University of Sydney, Sydney 2006, New South Wales, Australia
| | - Matthew P Padula
- The ithree Institute, University of Technology, Sydney 2007, New South Wales, Australia
| | - Jessica L Tacchi
- The ithree Institute, University of Technology, Sydney 2007, New South Wales, Australia
| | - Benjamin B A Raymond
- The ithree Institute, University of Technology, Sydney 2007, New South Wales, Australia
| | - Cheryl Jenkins
- NSW Department of Primary Industries, Elizabeth Macarthur Agricultural Institute, Camden 2567, New South Wales, Australia
| | - Stuart J Cordwell
- School of Molecular and Microbial Biosciences, University of Sydney, Sydney 2006, New South Wales, Australia
| | - F Chris Minion
- Veterinary Microbiology and Preventive Medicine, Iowa State University, Ames, Iowa 50011
| | - Mark J Walker
- School of Biological Sciences, University of Wollongong, Wollongong 2522, New South Wales, Australia; School of Chemistry and Molecular Biosciences and the Australian Infectious Diseases Research Centre, University of Queensland, Brisbane 4072, Queensland, Australia
| | - Steven P Djordjevic
- NSW Department of Primary Industries, Elizabeth Macarthur Agricultural Institute, Camden 2567, New South Wales, Australia; The ithree Institute, University of Technology, Sydney 2007, New South Wales, Australia.
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Nasopharyngeal colonization and invasive disease are enhanced by the cell wall hydrolases LytB and LytC of Streptococcus pneumoniae. PLoS One 2011; 6:e23626. [PMID: 21886805 PMCID: PMC3160309 DOI: 10.1371/journal.pone.0023626] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2011] [Accepted: 07/21/2011] [Indexed: 01/07/2023] Open
Abstract
Background Streptococcus pneumoniae is a common colonizer of the human nasopharynx and one of the major pathogens causing invasive disease worldwide. Dissection of the molecular pathways responsible for colonization, invasion, and evasion of the immune system will provide new targets for antimicrobial or vaccine therapies for this common pathogen. Methodology/Principal Findings We have constructed mutants lacking the pneumococcal cell wall hydrolases (CWHs) LytB and LytC to investigate the role of these proteins in different phases of the pneumococcal pathogenesis. Our results show that LytB and LytC are involved in the attachment of S. pneumoniae to human nasopharyngeal cells both in vitro and in vivo. The interaction of both proteins with phagocytic cells demonstrated that LytB and LytC act in concert avoiding pneumococcal phagocytosis mediated by neutrophils and alveolar macrophages. Furthermore, C3b deposition was increased on the lytC mutant confirming that LytC is involved in complement evasion. As a result, the lytC mutant showed a reduced ability to successfully cause pneumococcal pneumonia and sepsis. Bacterial mutants lacking both LytB and LytC showed a dramatically impaired attachment to nasopharyngeal cells as well as a marked degree of attenuation in a mouse model of colonization. In addition, C3b deposition and phagocytosis was more efficient for the double lytB lytC mutant and its virulence was greatly impaired in both systemic and pulmonary models of infection. Conclusions/Significance This study confirms that the CWHs LytB and LytC of S. pneumoniae are essential virulence factors involved in the colonization of the nasopharynx and in the progress of invasive disease by avoiding host immunity.
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Lapirattanakul J, Nakano K, Nomura R, Leelataweewud P, Chalermsarp N, Klaophimai A, Srisatjaluk R, Hamada S, Ooshima T. Multilocus sequence typing analysis of Streptococcus mutans strains with the cnm gene encoding collagen-binding adhesin. J Med Microbiol 2011; 60:1677-1684. [PMID: 21680768 DOI: 10.1099/jmm.0.033415-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Streptococcus mutans is one of the oral pathogens associated with infective endocarditis (IE). With respect to bacterial binding ability to the extracellular matrix, the Cnm protein, a cell surface collagen-binding adhesin of S. mutans, is known as one of the possible virulence factors with regard to IE. In this study, we aimed to determine the distribution of the cnm gene, which encodes Cnm, in a large number of clinical isolates of S. mutans from Thai subjects. Then, the cnm-positive strains were classified using a multilocus sequence typing (MLST) scheme, which we constructed previously. In addition, the data were analysed together with our previous MLST data of cnm-positive strains from Japan and Finland in order to evaluate the clonal relationship among S. mutans strains harbouring the cnm gene. The cnm gene was detected in 12.4 % of all 750 Thai isolates, and serotype f showed the highest rate of detection (54.5 %). According to the MLST data, two clonal complex groups were revealed as the important clones related to cnm-positive S. mutans from various origins of isolation. Moreover, the collagen-binding properties of S. mutans strains with the cnm gene were significantly greater than those of strains without the gene, although four cnm-negative strains classified into two sequence types (STs), ST110 and ST136, showed extremely high collagen-binding rates suggesting the presence of additional genes involved with collagen binding in these STs. Taken together, these results provided information on both epidemiological as well as evolutional aspects of S. mutans possessing the cnm gene.
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Affiliation(s)
- Jinthana Lapirattanakul
- Department of Oral Microbiology, Faculty of Dentistry, Mahidol University, Bangkok 10400, Thailand
| | - Kazuhiko Nakano
- Department of Pediatric Dentistry, Osaka University Graduate School of Dentistry, Osaka 565-0871, Japan
| | - Ryota Nomura
- Department of Pediatric Dentistry, Osaka University Graduate School of Dentistry, Osaka 565-0871, Japan
| | | | - Narumon Chalermsarp
- Department of Oral Medicine, Faculty of Dentistry, Mahidol University, Bangkok 10400, Thailand
| | - Arthit Klaophimai
- Department of Oral Microbiology, Faculty of Dentistry, Mahidol University, Bangkok 10400, Thailand
| | - Ratchapin Srisatjaluk
- Department of Oral Microbiology, Faculty of Dentistry, Mahidol University, Bangkok 10400, Thailand
| | - Shigeyuki Hamada
- Research Institute for Microbial Diseases, Osaka University, Thailand-Japan Research Collaboration Center on Emerging and Re-emerging Infection, Nonthaburi 11000, Thailand
| | - Takashi Ooshima
- Department of Pediatric Dentistry, Osaka University Graduate School of Dentistry, Osaka 565-0871, Japan
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49
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Lin IH, Liu TT, Teng YT, Wu HL, Liu YM, Wu KM, Chang CH, Hsu MT. Sequencing and comparative genome analysis of two pathogenic Streptococcus gallolyticus subspecies: genome plasticity, adaptation and virulence. PLoS One 2011; 6:e20519. [PMID: 21633709 PMCID: PMC3102119 DOI: 10.1371/journal.pone.0020519] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2011] [Accepted: 04/28/2011] [Indexed: 11/25/2022] Open
Abstract
Streptococcus gallolyticus infections in humans are often associated with bacteremia, infective endocarditis and colon cancers. The disease manifestations are different depending on the subspecies of S. gallolyticus causing the infection. Here, we present the complete genomes of S. gallolyticus ATCC 43143 (biotype I) and S. pasteurianus ATCC 43144 (biotype II.2). The genomic differences between the two biotypes were characterized with comparative genomic analyses. The chromosome of ATCC 43143 and ATCC 43144 are 2,36 and 2,10 Mb in length and encode 2246 and 1869 CDS respectively. The organization and genomic contents of both genomes were most similar to the recently published S. gallolyticus UCN34, where 2073 (92%) and 1607 (86%) of the ATCC 43143 and ATCC 43144 CDS were conserved in UCN34 respectively. There are around 600 CDS conserved in all Streptococcus genomes, indicating the Streptococcus genus has a small core-genome (constitute around 30% of total CDS) and substantial evolutionary plasticity. We identified eight and five regions of genome plasticity in ATCC 43143 and ATCC 43144 respectively. Within these regions, several proteins were recognized to contribute to the fitness and virulence of each of the two subspecies. We have also predicted putative cell-surface associated proteins that could play a role in adherence to host tissues, leading to persistent infections causing sub-acute and chronic diseases in humans. This study showed evidence that the S. gallolyticus still possesses genes making it suitable in a rumen environment, whereas the ability for S. pasteurianus to live in rumen is reduced. The genome heterogeneity and genetic diversity among the two biotypes, especially membrane and lipoproteins, most likely contribute to the differences in the pathogenesis of the two S. gallolyticus biotypes and the type of disease an infected patient eventually develops.
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Affiliation(s)
- I-Hsuan Lin
- Institute of BioMedical Informatics, National Yang-Ming University, Taipei, Taiwan
- Taiwan International Graduate Program, Academia Sinica, Taipei, Taiwan
| | - Tze-Tze Liu
- VGH Yang-Ming Genome Research Center, National Yang-Ming University, Taipei, Taiwan
| | - Yu-Ting Teng
- VGH Yang-Ming Genome Research Center, National Yang-Ming University, Taipei, Taiwan
| | - Hui-Lun Wu
- VGH Yang-Ming Genome Research Center, National Yang-Ming University, Taipei, Taiwan
| | - Yen-Ming Liu
- VGH Yang-Ming Genome Research Center, National Yang-Ming University, Taipei, Taiwan
| | - Keh-Ming Wu
- VGH Yang-Ming Genome Research Center, National Yang-Ming University, Taipei, Taiwan
| | - Chuan-Hsiung Chang
- Institute of BioMedical Informatics, National Yang-Ming University, Taipei, Taiwan
- Center for Systems and Synthetic Biology, National Yang-Ming University, Taipei, Taiwan
| | - Ming-Ta Hsu
- VGH Yang-Ming Genome Research Center, National Yang-Ming University, Taipei, Taiwan
- Institute of Biochemistry and Molecular Biology, National Yang-Ming University, Taipei, Taiwan
- * E-mail:
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Lack of the delta subunit of RNA polymerase increases virulence related traits of Streptococcus mutans. PLoS One 2011; 6:e20075. [PMID: 21625504 PMCID: PMC3098267 DOI: 10.1371/journal.pone.0020075] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2011] [Accepted: 04/25/2011] [Indexed: 01/21/2023] Open
Abstract
The delta subunit of the RNA polymerase, RpoE, maintains the transcriptional specificity in Gram-positive bacteria. Lack of RpoE results in massive changes in the transcriptome of the human dental caries pathogen Streptococcus mutans. In this study, we analyzed traits of the ΔrpoE mutant which are important for biofilm formation and interaction with oral microorganisms and human cells and performed a global phenotypic analysis of its physiological functions. The ΔrpoE mutant showed higher self-aggregation compared to the wild type and coaggregated with other oral bacteria and Candida albicans. It formed a biofilm with a different matrix structure and an altered surface attachment. The amount of the cell surface antigens I/II SpaP and the glucosyltransferase GtfB was reduced. The ΔrpoE mutant displayed significantly stronger adhesion to human extracellular matrix components, especially to fibronectin, than the wild type. Its adhesion to human epithelial cells HEp-2 was reduced, probably due to the highly aggregated cell mass. The analysis of 1248 physiological traits using phenotype microarrays showed that the ΔrpoE mutant metabolized a wider spectrum of carbon sources than the wild type and had acquired resistance to antibiotics and inhibitory compounds with various modes of action. The reduced antigenicity, increased aggregation, adherence to fibronection, broader substrate spectrum and increased resistance to antibiotics of the ΔrpoE mutant reveal the physiological potential of S. mutans and show that some of its virulence related traits are increased.
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