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Seers CA, Mahmud ASM, Huq NL, Cross KJ, Reynolds EC. Porphyromonas gingivalis laboratory strains and clinical isolates exhibit different distribution of cell surface and secreted gingipains. J Oral Microbiol 2020; 13:1858001. [PMID: 33391630 PMCID: PMC7733959 DOI: 10.1080/20002297.2020.1858001] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Background: The cell-surface cysteine proteinases RgpA, RgpB (Arg-gingipain), and Kgp (Lys-gingipain) are major virulence factors of P. gingivalis, a keystone pathogen in the development of destructive periodontal disease. The gingipains function as proteinases and transpeptidases utilising small peptides such as glycylglycine as acceptor molecules. However, the characteristics of the gingipains from most P. gingivalis strains have not been determined. Methods: We determined the phenotypes of a panel of P. gingivalis laboratory strains and global clinical isolates with respect to growth on blood agar plus whole-cell and vesicle-free culture supernatant (VFSN) Arg- and Lys-specific proteinase activities. Results: The P. gingivalis isolates exhibited different growth characteristics and hydrolysis of haemoglobin in solid media. Whole-cell Arg-gingipain Vmax varied 5.8-fold and the whole cell Lys-gingipain Vmax varied 2.1-fold across the strains. Furthermore, the P. gingivalis strains showed more than 107-fold variance in soluble Arg-gingipain activity in VFSN and more than 371-fold variance in soluble Lys-gingipain activity in VFSN. Glycylglycine and cysteine stimulated Arg- and Lys-specific cleavage activities of all strains. The stimulation by cysteine was in addition to its redox effect consistent with both glycylglycine and cysteine promoting transpeptidation.
Conclusion: The global P. gingivalis clinical isolates exhibit different Arg- and Lys‑gingipain activities with substantial variability in the level of soluble proteinases released into the environment.
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Affiliation(s)
- Christine A Seers
- Oral Health Cooperative Research Centre, Melbourne Dental School, Bio21 Institute, The University of Melbourne, Melbourne, Australia
| | - A Sayeed M Mahmud
- Oral Health Cooperative Research Centre, Melbourne Dental School, Bio21 Institute, The University of Melbourne, Melbourne, Australia
| | - N Laila Huq
- Oral Health Cooperative Research Centre, Melbourne Dental School, Bio21 Institute, The University of Melbourne, Melbourne, Australia
| | - Keith J Cross
- Oral Health Cooperative Research Centre, Melbourne Dental School, Bio21 Institute, The University of Melbourne, Melbourne, Australia
| | - Eric C Reynolds
- Oral Health Cooperative Research Centre, Melbourne Dental School, Bio21 Institute, The University of Melbourne, Melbourne, Australia
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Hirai K, Yamaguchi-Tomikawa T, Eguchi T, Maeda H, Takashiba S. Identification and Modification of Porphyromonas gingivalis Cysteine Protease, Gingipain, Ideal for Screening Periodontitis. Front Immunol 2020; 11:1017. [PMID: 32582160 PMCID: PMC7290125 DOI: 10.3389/fimmu.2020.01017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Accepted: 04/28/2020] [Indexed: 12/31/2022] Open
Abstract
Chronic periodontitis is an inflammatory disease caused by the formation of oral microbial biofilms. Periodontitis is associated with general health and not only oral diseases. Porphyromonas gingivalis is a well-known keystone pathogen for periodontitis and is associated with several systemic diseases, such as diabetes mellitus and Alzheimer's disease. We previously developed a system for screening periodontitis using P. gingivalis-specific serum immunoglobulin G (IgG) in an enzyme-linked immunosorbent assay with a sensitivity of 0.774 and a specificity of 0.586 and an area under the receiver operating characteristic curve of 0.708. However, the antigens elicited non-specific responses, since they were obtained from whole extracts of sonicated cultured bacteria. The purpose of this study was to identify antigens ideal for a sensitive and specific serum test. We identified the specific antigens using immunoaffinity columns immobilized with IgG antibodies from periodontitis patients. Liquid chromatography-tandem mass spectrometry identified 29 antigens from the elutes. Recombinant proteins for these candidates were synthesized using the wheat germ cell-free translation system and screened by dot blot analysis with serum from the columns. Three of the 16 candidates that reacted showed strongest affinities upon dot blot analysis; they included outer membrane protein 28, cysteine proteases, lysine gingipain Kgp, and arginine gingipain RgpA. Outer membrane protein 28 was not suitable for screening P. gingivalis infection because of its high false-negative rates. Kgp and RgpA were unstable antigens since they underwent self-digestion. They were made stable by substituting the active cysteine residues in Kgp and RgpA with alanine using site-directed mutagenesis. Using the modified antigens, we demonstrated that the patient serum IgG level against RgpA was the highest among all the antigens expressed in P. gingivalis. Moreover, the N-terminus of recombinant RgpA was excellent in differentiating between diseased and non-diseased states (with sensitivity of 0.85, specificity of 0.9, and area under the curve of 0.915). Although dot blot analysis was the only experiment used, the N-terminus of RgpA is an excellent antigen to immunologically test for P. gingivalis infection, especially for estimating the risks for periodontitis-associated systemic diseases. In conclusion, we have developed a P. gingivalis antigen for screening periodontitis.
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Affiliation(s)
- Kimito Hirai
- Department of Pathophysiology-Periodontal Science, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Tomoko Yamaguchi-Tomikawa
- Department of Pathophysiology-Periodontal Science, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | | | - Hiroshi Maeda
- Department of Endodontology, Osaka Dental University, Osaka, Japan
| | - Shogo Takashiba
- Department of Pathophysiology-Periodontal Science, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
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He X, Wang L, Li H, Zhang S, Wang Z, Jiang J, Xiao J, Wang F, Jiang K, Zhao P, Zhang A, Bi L, Guo D, Sun D. Screening of BHK-21 cellular proteins that interact with outer membrane protein 43K OMP of Fusobacterium necrophorum. Anaerobe 2020; 63:102184. [PMID: 32247918 DOI: 10.1016/j.anaerobe.2020.102184] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Revised: 02/24/2020] [Accepted: 03/03/2020] [Indexed: 11/27/2022]
Abstract
Fusobacterium necrophorum is a Gram negative, spore-free, anaerobic bacterium that can cause pyogenic and necrotic infections in animals and humans. It is a major bovine pathogen and causes hepatic abscesses, foot rot, and necrotic laryngitis. The 43K OMP of F. necrophorum is an outer membrane protein with molecular weight of 43 kDa, exhibiting similarity to pore-forming proteins of other Fusobacterium species that plays an important role in bacterial infections. However, the role of 43K OMP in F. necrophorum adhesion remains unknown. In this study, we evaluated whether the 43K OMP of F. necrophorum mediates adhesion to BHK-21 cells and performed a preliminary screen of the proteins that interact with 43K OMP of F. necrophorum by immunoprecipitation-mass spectrometry. The results showed that the natural 43K OMP and recombinant 43K OMP could bind to BHK-21 cells, and preincubation of F. necrophorum with an antibody against the recombinant 43K OMP of F. necrophorum decreased binding to BHK-21 cells. Seventy differential interacting proteins were successfully screened by immunoprecipitation-mass spectrometry. Among these seventy differential interacting proteins, seven cell membrane proteins and four extracellular matrix proteins shown to be relevant to bacteria adhesion through subcellular localization and single-molecule function analysis. These data increase our understanding of the pathogenesis of F. necrophorum and provide a new theoretical basis for the design of antimicrobial drugs against F. necrophorum.
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Affiliation(s)
- Xianjing He
- Heilongjiang Provincial Key Laboratory of Prevention and Control of Bovine Diseases, College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, 163319, China
| | - Lina Wang
- Heilongjiang Provincial Key Laboratory of Prevention and Control of Bovine Diseases, College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, 163319, China
| | - He Li
- Heilongjiang Provincial Key Laboratory of Prevention and Control of Bovine Diseases, College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, 163319, China
| | - Siyao Zhang
- Heilongjiang Provincial Key Laboratory of Prevention and Control of Bovine Diseases, College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, 163319, China
| | - Zhihui Wang
- Heilongjiang Provincial Key Laboratory of Prevention and Control of Bovine Diseases, College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, 163319, China
| | - Jiancheng Jiang
- Heilongjiang Provincial Key Laboratory of Prevention and Control of Bovine Diseases, College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, 163319, China
| | - Jiawei Xiao
- Heilongjiang Provincial Key Laboratory of Prevention and Control of Bovine Diseases, College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, 163319, China
| | - Fengfeng Wang
- Heilongjiang Provincial Key Laboratory of Prevention and Control of Bovine Diseases, College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, 163319, China
| | - Kai Jiang
- Heilongjiang Provincial Key Laboratory of Prevention and Control of Bovine Diseases, College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, 163319, China
| | - Pengyu Zhao
- Heilongjiang Provincial Key Laboratory of Prevention and Control of Bovine Diseases, College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, 163319, China
| | - Aihui Zhang
- Heilongjiang Provincial Key Laboratory of Prevention and Control of Bovine Diseases, College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, 163319, China
| | - Lan Bi
- Heilongjiang Provincial Key Laboratory of Prevention and Control of Bovine Diseases, College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, 163319, China
| | - Donghua Guo
- Heilongjiang Provincial Key Laboratory of Prevention and Control of Bovine Diseases, College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, 163319, China.
| | - Dongbo Sun
- Heilongjiang Provincial Key Laboratory of Prevention and Control of Bovine Diseases, College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, 163319, China.
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Abdi K, Chen T, Klein BA, Tai AK, Coursen J, Liu X, Skinner J, Periasamy S, Choi Y, Kessler BM, Palmer RJ, Gittis A, Matzinger P, Duncan MJ, Singh NJ. Mechanisms by which Porphyromonas gingivalis evades innate immunity. PLoS One 2017; 12:e0182164. [PMID: 28771533 PMCID: PMC5542538 DOI: 10.1371/journal.pone.0182164] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Accepted: 07/13/2017] [Indexed: 01/08/2023] Open
Abstract
The oral cavity is home to unique resident microbial communities whose interactions with host immunity are less frequently studied than those of the intestinal microbiome. We examined the stimulatory capacity and the interactions of two oral bacteria, Porphyromonas gingivalis (P. gingivalis) and Fusobacterium nucleatum (F. nucleatum), on Dendritic Cell (DC) activation, comparing them to the effects of the well-studied intestinal microbe Escherichia coli (E. coli). Unlike F. nucleatum and E. coli, P. gingivalis failed to activate DCs, and in fact silenced DC responses induced by F. nucleatum or E. coli. We identified a variant strain of P. gingivalis (W50) that lacked this immunomodulatory activity. Using biochemical approaches and whole genome sequencing to compare the two substrains, we found a point mutation in the hagA gene. This protein is though to be involved in the alteration of the PorSS/gingipain pathway, which regulates protein secretion into the extracellular environment. A proteomic comparison of the secreted products of the two substrains revealed enzymatic differences corresponding to this phenotype. We found that P. gingivalis secretes gingipain(s) that inactivate several key proinflammatory mediators made by DCs and/or T cells, but spare Interleukin-1 (IL-1) and GM-CSF, which can cause capillary leaks that serve as a source of the heme that P. gingivalis requires for its survival, and GM-CSF, which can cause epithelial-cell growth. Taken together, our results suggest that P. gingivalis has evolved potent mechanisms to modulate its virulence factors and dampen the innate immune response by selectively inactivating most proinflammatory cytokines.
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Affiliation(s)
- Kaveh Abdi
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, NIH, Rockville, Maryland, United States of America
- * E-mail:
| | - Tsute Chen
- Department of Microbiology, The Forsyth Institute, Cambridge, Massachusetts, United States of America
| | - Brian A. Klein
- Department of Microbiology, The Forsyth Institute, Cambridge, Massachusetts, United States of America
| | - Albert K. Tai
- TUCF Genomics, Tufts University School of Medicine, Boston, Massachusetts, United States of America
| | - Jill Coursen
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, NIH, Rockville, Maryland, United States of America
| | - Xiangdong Liu
- Laboratory of Immunoregulation, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, Maryland, United States of America
| | - Jeff Skinner
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, NIH, Rockville, Maryland, United States of America
| | - Saravanan Periasamy
- National Institute of Dental and Craniofacial Research, NIH, Bethesda, Maryland, United States of America
| | - Youngnim Choi
- Department of Oromaxillofacial Infection & Immunity, School of Dentistry and Dental Research Institute, Seoul National University, Seoul, Korea
| | - Benedikt M. Kessler
- Target Discovery Institute, Nuffield Department of Clinical Medicine Oxford University, Oxford, United Kingdom
| | - Robert J. Palmer
- National Institute of Dental and Craniofacial Research, NIH, Bethesda, Maryland, United States of America
| | - Apostolos Gittis
- Research Technologies Branch, National Institute of Allergy and Infectious Diseases, NIH, Rockville, Maryland, United States of America
| | - Polly Matzinger
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, NIH, Rockville, Maryland, United States of America
| | - Margaret J. Duncan
- Department of Microbiology, The Forsyth Institute, Cambridge, Massachusetts, United States of America
| | - Nevil J. Singh
- University of Maryland School of Medicine, Department of Microbiology & Immunology, Baltimore, Maryland United States of America
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Dashper SG, Mitchell HL, Seers CA, Gladman SL, Seemann T, Bulach DM, Chandry PS, Cross KJ, Cleal SM, Reynolds EC. Porphyromonas gingivalis Uses Specific Domain Rearrangements and Allelic Exchange to Generate Diversity in Surface Virulence Factors. Front Microbiol 2017; 8:48. [PMID: 28184216 PMCID: PMC5266723 DOI: 10.3389/fmicb.2017.00048] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2016] [Accepted: 01/06/2017] [Indexed: 12/13/2022] Open
Abstract
Porphyromonas gingivalis is a keystone pathogen of chronic periodontitis. The virulence of P. gingivalis is reported to be strain related and there are currently a number of strain typing schemes based on variation in capsular polysaccharide, the major and minor fimbriae and adhesin domains of Lys-gingipain (Kgp), amongst other surface proteins. P. gingivalis can exchange chromosomal DNA between strains by natural competence and conjugation. The aim of this study was to determine the genetic variability of P. gingivalis strains sourced from international locations over a 25-year period and to determine if variability in surface virulence factors has a phylogenetic basis. Whole genome sequencing was performed on 13 strains and comparison made to 10 previously sequenced strains. A single nucleotide polymorphism-based phylogenetic analysis demonstrated a shallow tri-lobed phylogeny. There was a high level of reticulation in the phylogenetic network, demonstrating extensive horizontal gene transfer between the strains. Two highly conserved variants of the catalytic domain of the major virulence factor the Kgp proteinase (KgpcatI and KgpcatII) were found. There were three variants of the fourth Kgp C-terminal cleaved adhesin domain. Specific variants of the cell surface proteins FimA, FimCDE, MfaI, RagAB, Tpr, and PrtT were also identified. The occurrence of all these variants in the P. gingivalis strains formed a mosaic that was not related to the SNP-based phylogeny. In conclusion P. gingivalis uses domain rearrangements and genetic exchange to generate diversity in specific surface virulence factors.
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Affiliation(s)
- Stuart G Dashper
- Oral Health Cooperative Research Centre, Melbourne Dental School, Bio21 Institute, University of Melbourne VIC, Australia
| | - Helen L Mitchell
- Oral Health Cooperative Research Centre, Melbourne Dental School, Bio21 Institute, University of Melbourne VIC, Australia
| | - Christine A Seers
- Oral Health Cooperative Research Centre, Melbourne Dental School, Bio21 Institute, University of Melbourne VIC, Australia
| | - Simon L Gladman
- Victorian Life Sciences Computation Initiative Carlton, VIC, Australia
| | - Torsten Seemann
- Victorian Life Sciences Computation Initiative Carlton, VIC, Australia
| | - Dieter M Bulach
- Victorian Life Sciences Computation Initiative Carlton, VIC, Australia
| | | | - Keith J Cross
- Oral Health Cooperative Research Centre, Melbourne Dental School, Bio21 Institute, University of Melbourne VIC, Australia
| | - Steven M Cleal
- Oral Health Cooperative Research Centre, Melbourne Dental School, Bio21 Institute, University of Melbourne VIC, Australia
| | - Eric C Reynolds
- Oral Health Cooperative Research Centre, Melbourne Dental School, Bio21 Institute, University of Melbourne VIC, Australia
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Osbourne DO, Aruni W, Roy F, Perry C, Sandberg L, Muthiah A, Fletcher HM. Role of vimA in cell surface biogenesis in Porphyromonas gingivalis. MICROBIOLOGY-SGM 2010; 156:2180-2193. [PMID: 20378652 PMCID: PMC3068682 DOI: 10.1099/mic.0.038331-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
The Porphyromonas gingivalis vimA gene has been previously shown to play a significant role in the biogenesis of gingipains. Further, in P. gingivalis FLL92, a vimA-defective mutant, there was increased auto-aggregation, suggesting alteration in membrane surface proteins. In order to determine the role of the VimA protein in cell surface biogenesis, the surface morphology of P. gingivalis FLL92 was further characterized. Transmission electron microscopy demonstrated abundant fimbrial appendages and a less well defined and irregular capsule in FLL92 compared with the wild-type. In addition, atomic force microscopy showed that the wild-type had a smoother surface compared with FLL92. Western blot analysis using anti-FimA antibodies showed a 41 kDa immunoreactive protein band in P. gingivalis FLL92 which was missing in the wild-type P. gingivalis W83 strain. There was increased sensitivity to globomycin and vancomycin in FLL92 compared with the wild-type. Outer membrane fractions from FLL92 had a modified lectin-binding profile. Furthermore, in contrast with the wild-type strain, nine proteins were missing from the outer membrane fraction of FLL92, while 20 proteins present in that fraction from FLL92 were missing in the wild-type strain. Taken together, these results suggest that the VimA protein affects capsular synthesis and fimbrial phenotypic expression, and plays a role in the glycosylation and anchorage of several surface proteins.
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Affiliation(s)
- Devon O Osbourne
- Division of Microbiology and Molecular Genetics, School of Medicine, Loma Linda University, Loma Linda, CA 92350, USA
| | - Wilson Aruni
- Division of Microbiology and Molecular Genetics, School of Medicine, Loma Linda University, Loma Linda, CA 92350, USA
| | - Francis Roy
- Division of Microbiology and Molecular Genetics, School of Medicine, Loma Linda University, Loma Linda, CA 92350, USA
| | - Christopher Perry
- Division of Biochemistry, School of Medicine, Loma Linda University, Loma Linda, CA 92350, USA
| | - Lawrence Sandberg
- Division of Biochemistry, School of Medicine, Loma Linda University, Loma Linda, CA 92350, USA
| | - Arun Muthiah
- Division of Microbiology and Molecular Genetics, School of Medicine, Loma Linda University, Loma Linda, CA 92350, USA
| | - Hansel M Fletcher
- Division of Microbiology and Molecular Genetics, School of Medicine, Loma Linda University, Loma Linda, CA 92350, USA
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Yoshimura F, Murakami Y, Nishikawa K, Hasegawa Y, Kawaminami S. Surface components of Porphyromonas gingivalis. J Periodontal Res 2008; 44:1-12. [PMID: 18973529 DOI: 10.1111/j.1600-0765.2008.01135.x] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
BACKGROUND AND OBJECTIVE Research on Porphyromonas gingivalis, a periodontopathogen, has provided a tremendous amount of information over the last 20 years, which may exceed in part than that on other closely related members in terms of phylogenetic as well as proteomic criteria, including Bacteroides fragilis and B. thetaiotaomicron as major anaerobic, opportunistic pathogens in the medical field. In this minireview, we focused on recent research findings concerning surface components such as outer membrane proteins and fimbriae, of P. gingivalis. MATERIAL AND METHODS Elucidation of the surface components in P. gingivalis was especially difficult because outer membrane proteins are tightly bound to lipopolysaccharide and they are resistant to dissociation and separation from each other, even during sodium dodecyl sulfate-polyacrylamide gel electrophoresis, unless samples are appropriately heated. In addition, P. gingivalis is asaccharolytic and therefore a potent proteolytic bacterium, another factor causing difficulty in research. The study of the surface components was carefully carried out considering these unique features in P. gingivalis when compared with other gram-negative bacteria, including Escherichia coli and Pseudomonas aeruginosa. RESULTS Separation of outer membrane proteins, and characterization of OmpA-like proteins and RagAB as major proteins, is described herein. Our recent findings on FimA and Mfa1 fimbriae, two unique appendages in this organism, and on their regulation of expression are also described briefly. CONCLUSION Surface components of P. gingivalis somehow have contact with host tissues and cells because of the outermost cell elements. Therefore, such bacterial components are potentially important in the occurrence of periodontal diseases.
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Affiliation(s)
- F Yoshimura
- Department of Microbiology, School of Dentistry, Aichi-Gakuin University, Nagoya, Aichi, Japan.
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