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AlKanderi S, AlFreeh M, Bhardwaj RG, Karched M. Sugar Substitute Stevia Inhibits Biofilm Formation, Exopolysaccharide Production, and Downregulates the Expression of Streptococcal Genes Involved in Exopolysaccharide Synthesis. Dent J (Basel) 2023; 11:267. [PMID: 38132405 PMCID: PMC10742993 DOI: 10.3390/dj11120267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Revised: 11/07/2023] [Accepted: 11/13/2023] [Indexed: 12/23/2023] Open
Abstract
BACKGROUND Acid production by sucrose fermentation disturbs the balance in dental plaque by lowering the oral pH. As a consequence of the profound effect of sucrose on caries initiation and progression, many studies have been directed towards finding non-cariogenic artificial sweeteners that can be used as a substitute to sucrose. Existing literature shows that dietary sucrose upregulates the expression of biofilm associated genes involved in exopolysaccharide (EPS) production. OBJECTIVE In this study, we aimed to investigate the effect of the sugar substitute stevia on biofilm formation, EPS secretion, and streptococcal genes encoding glucan-binding proteins (Gbps) and glucosyltransferases (Gtfs), which are essential for the synthesis of EPS. MATERIALS AND METHODS Streptococcus mutans and Streptococcus gordonii were grown as biofilm cultures with or without stevia and sucrose. Biomass was quantified for biofilm and EPS production by crystal violet staining and the phenol-sulfuric acid method, respectively. Expression of gtfB and gbpB genes was studied by RT-PCR. RESULTS The quantities of biofilm were significantly lower when grown in the presence of stevia compared to sucrose in both species (p < 0.05). The proportion of EPS in the biofilm pellet decreased with increasing concentrations of stevia in both species but remained nearly unchanged with sucrose with respect to the control. In both streptococcal species, exposure of stevia decreased the expression of gtfB and gbpB genes compared to sucrose (p < 0.05). In comparison to the untreated control, the expression was decreased in the presence of stevia in both species, while it increased 2.5- to 4-fold in S. mutans and 1.5- to 2.5-fold in S. gordonii in the presence of sucrose. CONCLUSION The ability of stevia to inhibit biofilm formation, reduce EPS production, and downregulate the expression of gtfB and gbpB genes in S. mutans and S. gordonii may have potential therapeutic applications in controlling dental plaques and caries.
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Affiliation(s)
| | | | | | - Maribasappa Karched
- Oral Microbiology Research Laboratory, Department of Bioclinical Sciences, College of Dentistry, Kuwait University, Safat 13110, Kuwait; (S.A.); (M.A.); (R.G.B.)
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2
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Park SY, Raka RN, Hui XL, Song Y, Sun JL, Xiang J, Wang J, Jin JM, Li XK, Xiao JS, Wu H. Six Spain Thymus essential oils composition analysis and their in vitro and in silico study against Streptococcus mutans. BMC Complement Med Ther 2023; 23:106. [PMID: 37020229 PMCID: PMC10074788 DOI: 10.1186/s12906-023-03928-7] [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: 01/10/2023] [Accepted: 03/20/2023] [Indexed: 04/07/2023] Open
Abstract
BACKGROUND Streptococcus mutans is a well-known oral pathogen that plays a critical role in the development of dental caries. Many studies have been directed to discover the chemical compounds present in natural products to inhibit the growth and biofilm formation activity of S. mutans. Thymus essential oils exhibit good inhibition on the growth and pathogenesis of S. mutans. However, details about the active compounds in Thymus essential oil and the inhibition mechanism still remain unclear. The aim of this study was to investigate the antimicrobial activity of 6 Thymus species (Three samples of Thymus vulgaris, two samples of Thymus zygis, and one sample of Thymus satureioides essential oils) on S. mutans, to identify the potential active components, and to reveal the underlying mechanism. METHODS The composition of Thymus essential oils was analyzed by gas chromatography-mass spectrometry. And its antibacterial effect was evaluated based on the bacterial growth, acid production, biofilm formation and genetic expression of virulence factors by S. mutans. Potential active components of the Thymus essential oil were identified using molecular docking and correlation analysis. RESULTS GC-MS analysis showed that the major components in the 6 Spain Thymus essential oils were linalool, α-terpineol, p-cymene, thymol and carvacrol. MIC and MBC analysis showed that 3 Thymus essential oils showed very sensitive antimicrobial activity, and were chosen for further analysis. The 3 Thymus essential oil exhibited a significant inhibitory effect on acid production, adherence and biofilm formation of S. mutans and the expression of virulence genes, such as brpA, gbpB, gtfB, gtfC, gtfD, vicR, spaP and relA. Correlation analysis showed that phenolic components, such as carvacrol and thymol, were positively related to DIZ value, which suggests that they are the potential antimicrobial components. Molecular docking between the Thymus essential oil components and virulence proteins also found that carvacrol and thymol exhibited strong binding affinity with functional domains of virulence genes. CONCLUSIONS Thymus essential oil showed significant inhibition against the growth and pathogenesis of S. mutans depending on their composition and concentration. And phenolic compounds, such as carvacrol and thymol, are the major active components. Thymus essential oil could be used in oral healthcare products as a potential anti-caries ingredient.
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Affiliation(s)
- Su-Yeon Park
- College of Chemical and Materials Engineering, Beijing Technology and Business University, Building No.1, Fucheng Road 11#, Haidian District, Beijing, 100048, China
| | - Rifat Nowshin Raka
- College of Chemical and Materials Engineering, Beijing Technology and Business University, Building No.1, Fucheng Road 11#, Haidian District, Beijing, 100048, China
| | - Xiu-Li Hui
- Department of Stomatology, General Hospital, Beijing, China
| | - Yang Song
- College of Chemical and Materials Engineering, Beijing Technology and Business University, Building No.1, Fucheng Road 11#, Haidian District, Beijing, 100048, China
| | - Jin-Long Sun
- Department of Stomatology, General Hospital, Beijing, China
| | - Jie Xiang
- College of Chemical and Materials Engineering, Beijing Technology and Business University, Building No.1, Fucheng Road 11#, Haidian District, Beijing, 100048, China
| | - Juan Wang
- College of Chemical and Materials Engineering, Beijing Technology and Business University, Building No.1, Fucheng Road 11#, Haidian District, Beijing, 100048, China
| | - Jian-Ming Jin
- College of Chemical and Materials Engineering, Beijing Technology and Business University, Building No.1, Fucheng Road 11#, Haidian District, Beijing, 100048, China
| | - Xu-Kai Li
- Shanxi Key Laboratory of Minor Crop Germplasm Innovation and Molecular Breeding, College of Life Sciences, Shanxi Agricultural University, Taigu, China
| | - Jun-Song Xiao
- College of Chemical and Materials Engineering, Beijing Technology and Business University, Building No.1, Fucheng Road 11#, Haidian District, Beijing, 100048, China
| | - Hua Wu
- College of Chemical and Materials Engineering, Beijing Technology and Business University, Building No.1, Fucheng Road 11#, Haidian District, Beijing, 100048, China.
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3
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Sun Y, Chen H, Xu M, He L, Mao H, Yang S, Qiao X, Yang D. Exopolysaccharides metabolism and cariogenesis of Streptococcus mutans biofilm regulated by antisense vicK RNA. J Oral Microbiol 2023; 15:2204250. [PMID: 37138664 PMCID: PMC10150615 DOI: 10.1080/20002297.2023.2204250] [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: 05/05/2023] Open
Abstract
Background Streptococcus mutans (S. mutans) is a pivotal cariogenic pathogen contributing to its multiple virulence factors, one of which is synthesizing exopolysaccharides (EPS). VicK, a sensor histidine kinase, plays a major role in regulating genes associated with EPS synthesis and adhesion. Here we first identified an antisense vicK RNA (ASvicK) bound with vicK into double-stranded RNA (dsRNA). Objective This study aims to investigate the effect and mechanism of ASvicK in the EPS metabolism and cariogenesis of S. mutans. Methods The phenotypes of biofilm were detected by scanning electron microscopy (SEM), gas chromatography-mass spectrometery (GC-MS) , gel permeation chromatography (GPC) , transcriptome analysis and Western blot. Co-immunoprecipitation (Co-ip) assay and enzyme activity experiment were adopted to investigate the mechanism of ASvicK regulation. Caries animal models were developed to study the relationship between ASvicK and cariogenicity of S. mutans. Results Overexpression of ASvicK can inhibit the growth of biofilm, reduce the production of EPS and alter genes and protein related to EPS metabolism. ASvicK can adsorb RNase III to regulate vicK and affect the cariogenicity of S. mutans. Conclusions ASvicK regulates vicK at the transcriptional and post-transcriptional levels, effectively inhibits EPS synthesis and biofilm formation and reduces its cariogenicity in vivo.
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Affiliation(s)
- Yuting Sun
- Department of Endodontics, Stomatological Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Chongqing, China
- Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, Chongqing, China
| | - Hong Chen
- Department of Endodontics, Stomatological Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Chongqing, China
- Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, Chongqing, China
| | - Mengmeng Xu
- Department of Endodontics, Stomatological Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Chongqing, China
- Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, Chongqing, China
| | - Liwen He
- Department of Endodontics, Stomatological Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Chongqing, China
- Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, Chongqing, China
| | - Hongchen Mao
- Department of Endodontics, Stomatological Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Chongqing, China
- Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, Chongqing, China
| | - Shiyao Yang
- Department of Endodontics, Stomatological Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Chongqing, China
- Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, Chongqing, China
| | - Xin Qiao
- Department of Endodontics, Stomatological Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Chongqing, China
- Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, Chongqing, China
| | - Deqin Yang
- Department of Endodontics, Stomatological Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Chongqing, China
- Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, Chongqing, China
- CONTACT Deqin Yang Department of Endodontics, Stomatological Hospital of Chongqing Medical University, Chongqing4404100, China
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Hasegawa T, Takenaka S, Oda M, Domon H, Hiyoshi T, Sasagawa K, Ohsumi T, Hayashi N, Okamoto Y, Yamamoto H, Ohshima H, Terao Y, Noiri Y. Sulfated vizantin causes detachment of biofilms composed mainly of the genus Streptococcus without affecting bacterial growth and viability. BMC Microbiol 2020; 20:361. [PMID: 33238885 PMCID: PMC7687742 DOI: 10.1186/s12866-020-02033-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Accepted: 11/03/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Sulfated vizantin, a recently developed immunostimulant, has also been found to exert antibiofilm properties. It acts not as a bactericide, but as a detachment-promoting agent by reducing the biofilm structural stability. This study aimed to investigate the mechanism underlying this activity and its species specificity using two distinct ex vivo oral biofilm models derived from human saliva. RESULTS The biofilm, composed mainly of the genus Streptococcus and containing 50 μM of sulfated vizantin, detached significantly from its basal surface with rotation at 500 rpm for only 15 s, even when 0.2% sucrose was supplied. Expression analyses for genes associated with biofilm formation and bacterial adhesion following identification of the Streptococcus species, revealed that a variety of Streptococcus species in a cariogenic biofilm showed downregulation of genes encoding glucosyltransferases involved in the biosynthesis of water-soluble glucan. The expression of some genes encoding surface proteins was also downregulated. Of the two quorum sensing systems involved in the genus Streptococcus, the expression of luxS in three species, Streptococcus oralis, Streptococcus gordonii, and Streptococcus mutans, was significantly downregulated in the presence of 50 μM sulfated vizantin. Biofilm detachment may be facilitated by the reduced structural stability due to these modulations. As a non-specific reaction, 50 μM sulfated vizantin decreased cell surface hydrophobicity by binding to the cell surface, resulting in reduced bacterial adherence. CONCLUSION Sulfated vizantin may be a candidate for a new antibiofilm strategy targeting the biofilm matrix while preserving the resident microflora.
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Affiliation(s)
- Taisuke Hasegawa
- Division of Cariology, Operative Dentistry and Endodontics, Faculty of Dentistry & Graduate School of Medical and Dental Sciences, Niigata University, 2-5274, Gakkocho-dori, Chuo-ku, Niigata, 951-8514, Japan
| | - Shoji Takenaka
- Division of Cariology, Operative Dentistry and Endodontics, Faculty of Dentistry & Graduate School of Medical and Dental Sciences, Niigata University, 2-5274, Gakkocho-dori, Chuo-ku, Niigata, 951-8514, Japan.
| | - Masataka Oda
- Department of Microbiology and Infection Control Science, Kyoto Pharmaceutical University, Kyoto, Japan
| | - Hisanori Domon
- Division of Microbiology and Infectious Diseases, Faculty of Dentistry & Graduate School of Medical and Dental sciences, Niigata University, Niigata, Japan
| | - Takumi Hiyoshi
- Division of Microbiology and Infectious Diseases, Faculty of Dentistry & Graduate School of Medical and Dental sciences, Niigata University, Niigata, Japan.,Division of Periodontology, Faculty of Dentistry & Graduate School of Medical and Dental sciences, Niigata University, Niigata, Japan
| | - Karin Sasagawa
- Division of Microbiology and Infectious Diseases, Faculty of Dentistry & Graduate School of Medical and Dental sciences, Niigata University, Niigata, Japan.,Division of Periodontology, Faculty of Dentistry & Graduate School of Medical and Dental sciences, Niigata University, Niigata, Japan
| | - Tatsuya Ohsumi
- Division of Cariology, Operative Dentistry and Endodontics, Faculty of Dentistry & Graduate School of Medical and Dental Sciences, Niigata University, 2-5274, Gakkocho-dori, Chuo-ku, Niigata, 951-8514, Japan
| | - Naoki Hayashi
- Department of Microbiology and Infection Control Science, Kyoto Pharmaceutical University, Kyoto, Japan
| | - Yasuko Okamoto
- Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Tokushima, Japan
| | - Hirofumi Yamamoto
- Department of Chemistry and Functional Molecule, Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Tokushima, Japan
| | - Hayato Ohshima
- Division of Anatomy and Cell Biology of Hard Tissue, Faculty of Dentistry & Graduate School of Medical and Dental sciences, Niigata University, Niigata, Japan
| | - Yutaka Terao
- Division of Microbiology and Infectious Diseases, Faculty of Dentistry & Graduate School of Medical and Dental sciences, Niigata University, Niigata, Japan
| | - Yuichiro Noiri
- Division of Cariology, Operative Dentistry and Endodontics, Faculty of Dentistry & Graduate School of Medical and Dental Sciences, Niigata University, 2-5274, Gakkocho-dori, Chuo-ku, Niigata, 951-8514, Japan
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5
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Glucan Binding Protein C of Streptococcus mutans Mediates both Sucrose-Independent and Sucrose-Dependent Adherence. Infect Immun 2018; 86:IAI.00146-18. [PMID: 29685986 DOI: 10.1128/iai.00146-18] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2018] [Accepted: 04/18/2018] [Indexed: 01/11/2023] Open
Abstract
The high-resolution structure of glucan binding protein C (GbpC) at 1.14 Å, a sucrose-dependent virulence factor of the dental caries pathogen Streptococcus mutans, has been determined. GbpC shares not only structural similarities with the V regions of AgI/II and SspB but also functional adherence to salivary agglutinin (SAG) and its scavenger receptor cysteine-rich domains (SRCRs). This is not only a newly identified function for GbpC but also an additional fail-safe binding mechanism for S. mutans Despite the structural similarities with S. mutans antigen I/II (AgI/II) and SspB of Streptococcus gordonii, GbpC remains unique among these surface proteins in its propensity to adhere to dextran/glucans. The complex crystal structure of GbpC with dextrose (β-d-glucose; Protein Data Bank ligand BGC) highlights exclusive structural features that facilitate this interaction with dextran. Targeted deletion mutant studies on GbpC's divergent loop region in the vicinity of a highly conserved calcium binding site confirm its role in biofilm formation. Finally, we present a model for adherence to dextran. The structure of GbpC highlights how artfully microbes have engineered the lectin-like folds to broaden their functional adherence repertoire.
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6
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Senpuku H, Yonezawa H, Yoneda S, Suzuki I, Nagasawa R, Narisawa N. SMU.940 regulates dextran-dependent aggregation and biofilm formation in Streptococcus mutans. Mol Oral Microbiol 2017; 33:47-58. [PMID: 28845576 DOI: 10.1111/omi.12196] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/22/2017] [Indexed: 11/30/2022]
Abstract
The oral bacterium Streptococcus mutans is the principal agent in the development of dental caries. Biofilm formation by S. mutans requires bacterial attachment, aggregation, and glucan formation on the tooth surface under sucrose supplementation conditions. Our previous microarray analysis of clinical strains identified 74 genes in S. mutans that were related to biofilm morphology; however, the roles of almost all of these genes in biofilm formation are poorly understood. We investigated the effects of 21 genes randomly selected from our previous study regarding S. mutans biofilm formation, regulation by the complement pathway, and responses to competence-stimulating peptide. Eight competence-stimulating peptide-dependent genes were identified, and their roles in biofilm formation and aggregation were examined by mutational analyses of the S. mutansUA159 strain. Of these eight genes, the inactivation of the putative hemolysin III family SMU.940 gene of S. mutansUA159 promoted rapid dextran-dependent aggregation and biofilm formation in tryptic soy broth without dextrose (TSB) with 0.25% glucose and slightly reduced biofilm formation in TSB with 0.25% sucrose. The SMU.940 mutant showed higher expression of GbpC and gbpC gene than wild-type. GbpC is known to be involved in the dextran-dependent aggregation of S. mutans. An SMU.940-gbpC double mutant strain was constructed in the SMU.940 mutant background. The gbpC mutation completely abolished the dextran-dependent aggregation of the SMU.940 mutant. In addition, the aggregation of the mutant was abrogated by dextranase. These findings suggest that SMU.940 controls GbpC expression, and contributes to the regulation of dextran-dependent aggregation and biofilm formation.
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Affiliation(s)
- Hidenobu Senpuku
- Department of Bacteriology I, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo, Japan
| | - Hideo Yonezawa
- Department of Bacteriology I, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo, Japan.,Department of Infectious Diseases, Kyorin University School of Medicine, Mitaka, Tokyo, Japan
| | - Saori Yoneda
- Department of Bacteriology I, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo, Japan.,Department of Microbiology, Faculty of Medicine, Kagawa University, Takamatsu, Japan
| | - Itaru Suzuki
- Department of Bacteriology I, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo, Japan.,Department of Pediatric Dentistry, Nihon University at Matsudo, Chiba, Japan
| | - Ryo Nagasawa
- Department of Bacteriology I, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo, Japan.,Graduate School of Science and Engineering, Hosei University, Shinjuku-ku, Tokyo, Japan
| | - Naoki Narisawa
- Department of Bacteriology I, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo, Japan.,Department of Food Science and Technology, College of Bioresource Sciences, Nihon University, Fujisawa, Kanagawa, Japan
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7
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Matsumoto-Nakano M. Role of Streptococcus mutans surface proteins for biofilm formation. JAPANESE DENTAL SCIENCE REVIEW 2017; 54:22-29. [PMID: 29628998 PMCID: PMC5884221 DOI: 10.1016/j.jdsr.2017.08.002] [Citation(s) in RCA: 124] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Revised: 06/30/2017] [Accepted: 08/01/2017] [Indexed: 11/15/2022] Open
Abstract
Streptococcus mutans has been implicated as a primary causative agent of dental caries in humans. An important virulence property of the bacterium is its ability to form biofilm known as dental plaque on tooth surfaces. In addition, this organism also produces glucosyltransferases, multiple glucan-binding proteins, protein antigen c, and collagen-binding protein, surface proteins that coordinate to produce dental plaque, thus inducing dental caries. Bacteria utilize quorum-sensing systems to modulate environmental stress responses. A major mechanism of response to signals is represented by the so called two-component signal transduction system, which enables bacteria to regulate their gene expression and coordinate activities in response to environmental stress. As for S. mutans, a signal peptide-mediated quorum-sensing system encoded by comCDE has been found to be a regulatory system that responds to cell density and certain environmental stresses by excreting a peptide signal molecule termed CSP (competence-stimulating peptide). One of its principal virulence factors is production of bacteriocins (peptide antibiotics) referred to as mutacins. Two-component signal transduction systems are commonly utilized by bacteria to regulate bacteriocin gene expression and are also related to biofilm formation by S. mutans.
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Affiliation(s)
- Michiyo Matsumoto-Nakano
- Department of Pediatric Dentistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1, Shikata-cho, Kita-ku, Okayama, Japan
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8
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Lapirattanakul J, Takashima Y, Tantivitayakul P, Maudcheingka T, Leelataweewud P, Nakano K, Matsumoto-Nakano M. Cariogenic properties of Streptococcus mutans clinical isolates with sortase defects. Arch Oral Biol 2017; 81:7-14. [PMID: 28458044 DOI: 10.1016/j.archoralbio.2017.04.018] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Revised: 02/27/2017] [Accepted: 04/17/2017] [Indexed: 12/30/2022]
Abstract
OBJECTIVE In Streptococcus mutans, a Gram-positive pathogen of dental caries, several surface proteins are anchored by the activity of sortase enzyme. Although various reports have shown that constructed S. mutans mutants deficient of sortase as well as laboratory reference strains with a sortase gene mutation have low cariogenic potential, no known studies have investigated clinical isolates with sortase defects. Here, we examined the cariogenic properties of S. mutans clinical isolates with sortase defects as well as caries status in humans harboring such defective isolates. DESIGN Sortase-defective clinical isolates were evaluated for biofilm formation, sucrose-dependent adhesion, stress-induced dextran-dependent aggregation, acid production, and acid tolerance. Additionally, caries indices of subjects possessing such defective isolates were determined. RESULTS Our in vitro results indicated that biofilm with a lower quantity was formed by sortase-defective as compared to non-defective isolates. Moreover, impairments of sucrose-dependent adhesion and stress-induced dextran-dependent aggregation were found among the isolates with defects, whereas no alterations were seen in regard to acid production or tolerance. Furthermore, glucan-binding protein C, a surface protein anchored by sortase activity, was predominantly detected in culture supernatants of all sortase-defective S. mutans isolates. Although the sortase-defective isolates showed lower cariogenic potential because of a reduction in some cariogenic properties, deft/DMFT indices revealed that all subjects harboring those isolates had caries experience. CONCLUSIONS Our findings suggest the impairment of cariogenic properties in S. mutans clinical isolates with sortase defects, though the detection of these defective isolates seemed not to imply low caries risk in the subjects harboring them.
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Affiliation(s)
- Jinthana Lapirattanakul
- Department of Oral Microbiology, Faculty of Dentistry, Mahidol University, Bangkok, 10400, Thailand.
| | - Yukiko Takashima
- Department of Pediatric Dentistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, 700-8525, Japan
| | - Pornpen Tantivitayakul
- Department of Oral Microbiology, Faculty of Dentistry, Mahidol University, Bangkok, 10400, Thailand
| | - Thaniya Maudcheingka
- 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
| | - Michiyo Matsumoto-Nakano
- Department of Pediatric Dentistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, 700-8525, Japan
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Takenaka S, Oda M, Domon H, Ohsumi T, Suzuki Y, Ohshima H, Yamamoto H, Terao Y, Noiri Y. Vizantin inhibits bacterial adhesion without affecting bacterial growth and causes Streptococcus mutans biofilm to detach by altering its internal architecture. Biochem Biophys Res Commun 2016; 480:173-179. [PMID: 27742478 DOI: 10.1016/j.bbrc.2016.10.021] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Accepted: 10/09/2016] [Indexed: 12/14/2022]
Abstract
An ideal antibiofilm strategy is to control both in the quality and quantity of biofilm while maintaining the benefits derived from resident microflora. Vizantin, a recently developed immunostimulating compound, has also been found to have antibiofilm property. This study evaluated the influence on biofilm formation of Streptococcus mutans in the presence of sulfated vizantin and biofilm development following bacterial adhesion on a hydroxyapatite disc coated with sulfated vizantin. Supplementation with sulfated vizantin up to 50 μM did not affect either bacterial growth or biofilm formation, whereas 50 μM sulfated vizantin caused the biofilm to readily detach from the surface. Sulfated vizantin at the concentration of 50 μM upregulated the expression of the gtfB and gtfC genes, but downregulated the expression of the gtfD gene, suggesting altered architecture in the biofilm. Biofilm development on the surface coated with sulfated vizantin was inhibited depending on the concentration, suggesting prevention from bacterial adhesion. Among eight genes related to bacterial adherence in S. mutans, expression of gtfB and gtfC was significantly upregulated, whereas the expression of gtfD, GbpA and GbpC was downregulated according to the concentration of vizantin, especially with 50 μM vizantin by 0.8-, 0.4-, and 0.4-fold, respectively. These findings suggest that sulfated vizantin may cause structural degradation as a result of changing gene regulation related to bacterial adhesion and glucan production of S. mutans.
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Affiliation(s)
- Shoji Takenaka
- Division of Cariology, Operative Dentistry and Endodontics, Niigata University Graduate School of Medical and Dental Sciences, 2-5274, Gakkocho-dori, Chuo-ku, Niigata, 951-8514, Japan.
| | - Masataka Oda
- Division of Microbiology and Infectious Diseases, Niigata University Graduate School of Medical and Dental Sciences, 2-5274, Gakkocho-dori, Chuo-ku, Niigata, 951-8514, Japan
| | - Hisanori Domon
- Division of Microbiology and Infectious Diseases, Niigata University Graduate School of Medical and Dental Sciences, 2-5274, Gakkocho-dori, Chuo-ku, Niigata, 951-8514, Japan
| | - Tatsuya Ohsumi
- Division of Cariology, Operative Dentistry and Endodontics, Niigata University Graduate School of Medical and Dental Sciences, 2-5274, Gakkocho-dori, Chuo-ku, Niigata, 951-8514, Japan
| | - Yuki Suzuki
- Division of Cariology, Operative Dentistry and Endodontics, Niigata University Graduate School of Medical and Dental Sciences, 2-5274, Gakkocho-dori, Chuo-ku, Niigata, 951-8514, Japan
| | - Hayato Ohshima
- Division of Anatomy and Cell Biology of Hard Tissue, Niigata University Graduate School of Medical and Dental Sciences, 2-5274, Gakkocho-dori, Chuo-ku, Niigata, 951-8514, Japan
| | - Hirofumi Yamamoto
- Department of Chemistry and Functional Molecule, Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Yamashiro-cho, Tokushima, 770-8514, Japan
| | - Yutaka Terao
- Division of Microbiology and Infectious Diseases, Niigata University Graduate School of Medical and Dental Sciences, 2-5274, Gakkocho-dori, Chuo-ku, Niigata, 951-8514, Japan
| | - Yuichiro Noiri
- Division of Cariology, Operative Dentistry and Endodontics, Niigata University Graduate School of Medical and Dental Sciences, 2-5274, Gakkocho-dori, Chuo-ku, Niigata, 951-8514, Japan
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10
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Takashima Y, Fujita K, Ardin A, Nagayama K, Nomura R, Nakano K, Matsumoto-Nakano M. Characterization of the dextran-binding domain in the glucan-binding protein C of Streptococcus mutans. J Appl Microbiol 2015; 119:1148-57. [DOI: 10.1111/jam.12895] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Revised: 05/22/2015] [Accepted: 06/09/2015] [Indexed: 11/30/2022]
Affiliation(s)
- Y. Takashima
- Department of Pediatric Dentistry; Okayama University Graduate School of Medicine; Dentistry and Pharmaceutical Sciences; Kita-ku Okayama Japan
| | - K. Fujita
- Department of Pediatric Dentistry; Okayama University Graduate School of Medicine; Dentistry and Pharmaceutical Sciences; Kita-ku Okayama Japan
| | - A.C. Ardin
- Department of Pediatric Dentistry; Osaka University Graduate School of Dentistry; Suita Osaka Japan
| | - K. Nagayama
- Department of Pediatric Dentistry; Osaka University Graduate School of Dentistry; Suita Osaka Japan
| | - R. Nomura
- Department of Pediatric Dentistry; Osaka University Graduate School of Dentistry; Suita Osaka Japan
| | - K. Nakano
- Department of Pediatric Dentistry; Osaka University Graduate School of Dentistry; Suita Osaka Japan
| | - M. Matsumoto-Nakano
- Department of Pediatric Dentistry; Okayama University Graduate School of Medicine; Dentistry and Pharmaceutical Sciences; Kita-ku Okayama Japan
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Regulation of recombination between gtfB/gtfC genes in Streptococcus mutans by recombinase A. ScientificWorldJournal 2013; 2013:405075. [PMID: 23476132 PMCID: PMC3586492 DOI: 10.1155/2013/405075] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2012] [Accepted: 01/14/2013] [Indexed: 11/18/2022] Open
Abstract
Streptococcus mutans produces 3 types of glucosyltransferases (GTFs), whose cooperative action is essential for cellular adhesion. The recombinase A (RecA) protein is required for homologous recombination. In our previous study, we isolated several strains with a smooth colony morphology and low GTF activity, characteristics speculated to be derived from the GTF fusions. The purpose of the present study was to investigate the mechanism of those fusions. S. mutans strain MT8148 was grown in the presence of recombinant RecA (rRecA) protein, after which smooth colonies were isolated. The biological functions and sequences of the gtfB and gtfC genes of this as well as other clinical strains were determined. The sucrose-dependent adherence rates of those strains were reduced as compared to that of MT8148. Determination of the sequences of the gtfB and gtfC genes showed that an approximately 3500 bp region was deleted from the area between them. Furthermore, expression of the recA gene was elevated in those strains as compared to MT8148. These results suggest that RecA has an important role in fusions of gtfB and gtfC genes, leading to alteration of colony morphology and reduction in sucrose-dependent adhesion.
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Phylogenetic analysis of glucosyltransferases and implications for the coevolution of mutans streptococci with their mammalian hosts. PLoS One 2013; 8:e56305. [PMID: 23457545 PMCID: PMC3572963 DOI: 10.1371/journal.pone.0056305] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2012] [Accepted: 01/08/2013] [Indexed: 11/19/2022] Open
Abstract
Glucosyltransferases (Gtfs) catalyze the synthesis of glucans from sucrose and are produced by several species of lactic-acid bacteria. The oral bacterium Streptococcus mutans produces large amounts of glucans through the action of three Gtfs. GtfD produces water-soluble glucan (WSG), GtfB synthesizes water-insoluble glucans (WIG) and GtfC produces mainly WIG but also WSG. These enzymes, especially those synthesizing WIG, are of particular interest because of their role in the formation of dental plaque, an environment where S. mutans can thrive and produce lactic acid, promoting the formation of dental caries. We sequenced the gtfB, gtfC and gtfD genes from several mutans streptococcal strains isolated from the oral cavity of humans and searched for their homologues in strains isolated from chimpanzees and macaque monkeys. The sequence data were analyzed in conjunction with the available Gtf sequences from other bacteria in the genera Streptococcus, Lactobacillus and Leuconostoc to gain insights into the evolutionary history of this family of enzymes, with a particular emphasis on S. mutans Gtfs. Our analyses indicate that streptococcal Gtfs arose from a common ancestral progenitor gene, and that they expanded to form two clades according to the type of glucan they synthesize. We also show that the clade of streptococcal Gtfs synthesizing WIG appeared shortly after the divergence of viviparous, dentate mammals, which potentially contributed to the formation of dental plaque and the establishment of several streptococci in the oral cavity. The two S. mutans Gtfs capable of WIG synthesis, GtfB and GtfC, are likely the product of a gene duplication event. We dated this event to coincide with the divergence of the genomes of ancestral early primates. Thus, the acquisition and diversification of S. mutans Gtfs predates modern humans and is unrelated to the increase in dietary sucrose consumption.
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Fujita K, Matsumoto-Nakano M, Inagaki S, Ooshima T. Biological functions of glucan-binding protein B of Streptococcus mutans. ACTA ACUST UNITED AC 2008; 22:289-92. [PMID: 17803624 DOI: 10.1111/j.1399-302x.2007.00351.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
INTRODUCTION Streptococcus mutans has been implicated as a major causative agent of dental caries in humans. Bacterial components associated with the adhesion phase of S. mutans include glucosyltransferases, protein antigen C and proteins that bind glucan. At least four glucan-binding proteins (Gbp) have been identified; GbpA, GbpB, GbpC and GbpD. METHODS In our previous study, the contributions of GbpA and GbpC to the virulence of S. mutans were investigated; however, the biological function of GbpB and its role in the virulence of S. mutans remain to be elucidated. Using a GbpB-deficient mutant strain (BD1), we demonstrated in the present study that GbpB has a role in the biology of S. mutans. RESULTS The growth rate of BD1 was lower than that of other strains, while it was also shown to be less susceptible to phagocytosis and to form longer chains than the parental strain MT8148. In addition, electron microscope observations of the cell surfaces of BD1 showed that the cell-wall layers were obscure. CONCLUSION These results suggest that GbpB may have an important role in cell-wall construction and be involved in cell separation and cell maintenance.
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Affiliation(s)
- K Fujita
- Department of Pediatric Dentistry, Osaka University Graduate School of Dentistry, Osaka, Japan
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14
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Cross SE, Kreth J, Zhu L, Sullivan R, Shi W, Qi F, Gimzewski JK. Nanomechanical properties of glucans and associated cell-surface adhesion of Streptococcus mutans probed by atomic force microscopy under in situ conditions. MICROBIOLOGY-SGM 2007; 153:3124-3132. [PMID: 17768255 DOI: 10.1099/mic.0.2007/007625-0] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
This study used atomic force microscopy (AFM) to probe the local cell-surface interactions associated with the glucan polymers of Streptococcus mutans, the macromolecules most commonly attributed to the virulence of this microbe. In situ force spectroscopy was used to quantitatively probe and correlate cell-surface adhesion and dynamics with S. mutans UA140 wild-type and five glucosyltransferase mutants. Adhesion between the tooth surface and S. mutans is largely mediated by glucan production from sucrose via three glucosyltransferases (Gtfs; GtfB, GtfC and GtfD). To monitor the contribution of these particular Gtfs, isogenic mutants of S. mutans were constructed by specific gene inactivation and compared to the wild-type under sucrose and non-sucrose conditions. We report direct measurement of the mechanical properties associated with glucan macromolecules demonstrating that the local adhesion strength increases in a time-dependent process, with a decrease in the average number of rupture events. This finding suggests that S. mutans attaches mainly through glucans to surfaces in the presence of sucrose. In addition, a possible role of the Gtf proteins in sucrose-independent attachment is supported by the decreased adhesion properties of the GtfBCD mutant compared to the wild-type.
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Affiliation(s)
- Sarah E Cross
- UCLA Institute for Cell Mimetic Space Exploration, Los Angeles, CA 90095, USA
- UCLA Department of Chemistry and Biochemistry, Los Angeles, CA 90095, USA
| | - Jens Kreth
- UCLA School of Dentistry, Los Angeles, CA 90095, USA
| | - Lin Zhu
- UCLA School of Dentistry, Los Angeles, CA 90095, USA
| | | | - Wenyuan Shi
- UCLA Molecular Biology Institute, Los Angeles, CA 90095, USA
- UCLA School of Dentistry, Los Angeles, CA 90095, USA
| | - Fengxia Qi
- UCLA School of Dentistry, Los Angeles, CA 90095, USA
| | - James K Gimzewski
- UCLA Institute for Cell Mimetic Space Exploration, Los Angeles, CA 90095, USA
- UCLA Department of Chemistry and Biochemistry, Los Angeles, CA 90095, USA
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Autoinducer-2-regulated genes in Streptococcus mutans UA159 and global metabolic effect of the luxS mutation. J Bacteriol 2007; 190:401-15. [PMID: 17981981 DOI: 10.1128/jb.01086-07] [Citation(s) in RCA: 103] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Autoinducer 2 (AI-2) is the only species-nonspecific autoinducer known in bacteria and is produced by both gram-negative and gram-positive organisms. Consequently, it is proposed to function as a universal quorum-sensing signal for interaction between bacterial species. AI-2 is produced as the by-product of a metabolic transformation carried out by the LuxS enzyme. To separate the metabolic function of the LuxS enzyme from the signaling role of AI-2, we carried out a global transcriptome analysis of a luxS null mutant culture of Streptococcus mutans UA159, an important cariogenic bacterium and a crucial component of the dental plaque biofilm community, in comparison to a luxS null mutant culture supplemented with chemically pure 4,5-dihydroxy-2,3-pentanedione, the precursor of AI-2. The data revealed fundamental changes in gene expression affecting 585 genes (30% of the genome) which could not be restored by the signal molecule AI-2 and are therefore not caused by quorum sensing but by lack of the transformation carried out by the LuxS enzyme in the activated methyl cycle. All functional classes of enzymes were affected, including genes known to be important for biofilm formation, bacteriocin synthesis, competence, and acid tolerance. At the same time, 59 genes were identified whose transcription clearly responded to the addition of AI-2. Some of them were related to protein synthesis, stress, and cell division. Three membrane transport proteins were upregulated which are not related to any of the known AI-2 transporters. Three transcription factors were identified whose transcription was stimulated repeatedly by AI-2 addition during growth. Finally, a global regulatory protein, the delta subunit of the RNA polymerase (rpoE), was induced 147-fold by AI-2, representing the largest differential gene expression observed. The data show that many phenotypes related to the luxS mutation cannot be ascribed to quorum sensing and have identified for the first time regulatory proteins potentially mediating AI-2-based signaling in gram-positive bacteria.
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Kagami A, Okamoto-Shibayama K, Yamamoto Y, Sato Y, Kizaki H. One of two gbpC gene homologues is involved in dextran-dependent aggregation of Streptococcus sobrinus. ACTA ACUST UNITED AC 2007; 22:240-7. [PMID: 17600535 DOI: 10.1111/j.1399-302x.2006.00347.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
INTRODUCTION Streptococcus sobrinus exhibits marked dextran-dependent aggregation mediated by glucan-binding proteins (GBPs). In contrast to Streptococcus mutans, in which the gbpC gene responsible for dextran-dependent aggregation of this organism has been characterized, genes encoding the S. sobrinus GBPs have not yet been identified. METHODS Recently, we identified the gbpC gene homologue from Streptococcus macacae using polymerase chain reaction primers based on the conserved regions of the gbpC sequence exhibiting intraspecies variations. This method was applied to amplify a S. sobrinus homologue. RESULTS Unexpectedly, two gbpC gene homologues were identified in S. sobrinus strain 100-4. One homologue, named gbpC, was more similar to the S. mutans gbpC gene than the other and was approximately half the molecular size of its homologue with similar regions interrupted by several non-similar stretches. However, the dextran-binding activity of the protein expressed from gbpC in Escherichia coli was not detected in contrast to the other homologue, a protein designated as Dbl, expressing this activity. The gbpC gene was shown to be intact on the chromosome of strain OMZ176, which does not exhibit dextran-dependent aggregation, while the dbl gene of this strain contained a single adenine nucleotide insertion at approximately one-third the distance from the 5'-end. The insertion mutation in the dbl gene resulted in translation of a premature protein missing its LPXTG sequence signature sequence of the wall-anchored proteins. CONCLUSION These results suggest that the dbl gene is very likely responsible for S. sobrinus dextran-dependent aggregation.
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Affiliation(s)
- A Kagami
- Department of Biochemistry and Oral Health Science Centre, Tokyo Dental College, Mihama-ku, Chiba City, Japan
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17
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Abstract
Streptococcus mutans, the principal causative agent of dental caries, produces four glucan-binding proteins (Gbp) that play major roles in bacterial adherence and pathogenesis. One of these proteins, GbpC, is an important cell surface protein involved in biofilm formation. GbpC is also important for cariogenesis, bacteremia, and infective endocarditis. In this study, we examined the regulation of gbpC expression in S. mutans strain UA159. We found that gbpC expression attains the maximum level at mid-exponential growth phase, and the half-life of the transcript is less than 2 min. Expression from PgbpC was measured using a PgbpC-gusA transcriptional fusion reporter and was analyzed under various stress conditions, including thermal, osmotic, and acid stresses. Expression of gbpC is induced under conditions of thermal stress but is repressed during growth at low pH, whereas osmotic stress had no effect on expression from PgbpC. The results from the expression analyses were further confirmed using semiquantitative reverse transcription-PCR analysis. Our results also reveal that CovR, a global response regulator in many Streptococcus spp., represses gbpC expression at the transcriptional level. We demonstrated that purified CovR protein binds directly to the promoter region of PgbpC to repress gbpC expression. Using a DNase I protection assay, we showed that CovR binds to DNA sequences surrounding PgbpC from bases -68 to 28 (where base 1 is the start of transcription). In summary, our results indicate that various stress conditions modulate the expression of gbpC and that CovR negatively regulates the expression of the gbpC gene by directly binding to the promoter region.
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Affiliation(s)
- Indranil Biswas
- Basic Biomedical Sciences, University of South Dakota, Lee Medical Building, 414 E. Clark Street, Vermillion, SD 57069, USA.
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Matsumoto-Nakano M, Fujita K, Ooshima T. Comparison of glucan-binding proteins in cariogenicity of Streptococcus mutans. ACTA ACUST UNITED AC 2007; 22:30-5. [PMID: 17241168 DOI: 10.1111/j.1399-302x.2007.00318.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Streptococcus mutans has been implicated as a primary causative agent of dental caries in humans. Bacterial components associated with the adhesion phase of S. mutans include cell-associated and cell-free glucosyltransferases (GTFs), as well as protein antigen c and proteins that bind glucan. At least four types of S. mutans glucan-binding protein (Gbp) have been identified; GbpA, GbpB, GbpC and GbpD. In the present study, GbpA-, GbpB- and GbpC-deficient mutants (AD1, BD1 and CD1, respectively) were constructed, and their cariogenic properties were evaluated by comparing them to those of their parent strain MT8148. All of the Gbp mutants showed lower levels of dextran binding, while the sucrose-dependent adhesion levels of AD1 and CD1 were lower than in the parental strain. The expression of each GTF was detected in the Gbp mutants, however, they had lower levels of cell-free-GTF activity than the parental strain. On the other hand, in acid tolerance assays, BD1 was the most sensitive among all of the tested strains. These results suggest that GbpA and GbpC in S. mutans have strong relationships with cariogenicity, while GbpB may have another biological function.
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Affiliation(s)
- M Matsumoto-Nakano
- Department of Pediatric Dentistry, Osaka University Graduate School of Dentistry, Osaka, Japan
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