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Anselmi NK, Vanyo ST, Clark ND, Rodriguez DML, Jones MM, Rosenthal S, Patel D, Marconi RT, Visser MB. Topology and functional characterization of major outer membrane proteins of Treponema maltophilum and Treponema lecithinolyticum. Mol Oral Microbiol 2024. [PMID: 39263909 DOI: 10.1111/omi.12484] [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: 05/09/2024] [Revised: 08/21/2024] [Accepted: 08/22/2024] [Indexed: 09/13/2024]
Abstract
Numerous Treponema species are prevalent in the dysbiotic subgingival microbial community during periodontitis. The major outer sheath protein is a highly expressed virulence factor of the well-characterized species Treponema denticola. Msp forms an oligomeric membrane protein complex with adhesin and porin properties and contributes to host-microbial interaction. Treponema maltophilum and Treponema lecithinolyticum species are also prominent during periodontitis but are relatively understudied. Msp-like membrane surface proteins exist in T. maltophilum (MspA) and T. lecithinolyticum (MspTL), but limited information exists regarding their structural features or functionality. Protein profiling reveals numerous differences between these species, but minimal differences between strains of the same species. Using protein modeling tools, we predict MspA and MspTL monomeric forms to be large β-barrel structures composed of 20 all-next-neighbor antiparallel β strands which most likely adopt a homotrimer formation. Using cell fractionation, Triton X-114 phase partitioning, heat modifiability, and chemical and detergent release assays, we found evidence of amphiphilic integral membrane-associated oligomerization for both native MspA and MspTL in intact spirochetes. Proteinase K accessibility and immunofluorescence assays demonstrate surface exposure of MspA and MspTL. Functionally, purified recombinant MspA or MspTL monomer proteins can impair neutrophil chemotaxis. Expressions of MspA or MspTL with a PelB leader sequence in Escherichia coli also demonstrate surface exposure and can impair neutrophil chemotaxis in an in vivo air pouch model of inflammation. Collectively, our data demonstrate that MspA and MspTL membrane proteins can contribute to pathogenesis of these understudied oral spirochete species.
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Affiliation(s)
- Natalie K Anselmi
- Department of Oral Biology, School of Dental Medicine, University at Buffalo, The State University of New York, Buffalo, New York, USA
| | - Stephen T Vanyo
- Department of Oral Biology, School of Dental Medicine, University at Buffalo, The State University of New York, Buffalo, New York, USA
| | - Nicholas D Clark
- Department of Structural Biology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, The State University of New York, Buffalo, New York, USA
| | - Dayron M Leyva Rodriguez
- Department of Oral Biology, School of Dental Medicine, University at Buffalo, The State University of New York, Buffalo, New York, USA
| | - Megan M Jones
- Department of Oral Biology, School of Dental Medicine, University at Buffalo, The State University of New York, Buffalo, New York, USA
| | - Sara Rosenthal
- Department of Oral Biology, School of Dental Medicine, University at Buffalo, The State University of New York, Buffalo, New York, USA
| | - Dhara Patel
- Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, Richmond, Virginia, USA
| | - Richard T Marconi
- Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, Richmond, Virginia, USA
| | - Michelle B Visser
- Department of Oral Biology, School of Dental Medicine, University at Buffalo, The State University of New York, Buffalo, New York, USA
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Smiline Girija AS. Moonlighting proteins [ML proteins]: The pandora's box of insidious oro-dental diseases. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2023; 1870:119435. [PMID: 36738892 DOI: 10.1016/j.bbamcr.2023.119435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Accepted: 01/27/2023] [Indexed: 02/05/2023]
Abstract
Oral pathogens survive in the harsh niche of the oral microbiome on account of a plethora of moonlighting [ML] proteins that can multitask in the oro-mucosal layers. ML proteins are considered as the complex protein hyperspace expressed in many oral bacterial pathogens and encompass many hypothetical and experimentally evidenced proteins that can efficiently assist in the initiation and progression of various oro-dental infections. With the propensity of multi-drug resistance and biofilm formation, unravelling the mysterious functions associated with the oral ML proteins could be essential in targeting the vital oral bacteria and their associated infections. This commentary thus throws insights onto the key clues on various ML proteins that can be considered for the development of therapeutic versatility to curtail the complications caused by various oral bacterial species.
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Affiliation(s)
- A S Smiline Girija
- Department of Microbiology, Saveetha Dental College and Hospitals, Saveetha Institute of Medical and Technical Sciences [SIMATS], Chennai 600077, Tamilnadu, India.
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Kokubu E, Kikuchi Y, Okamoto-Shibayama K, Ishihara K. Effect of Treponema Denticola Infection on Epithelial Cells. THE BULLETIN OF TOKYO DENTAL COLLEGE 2022; 63:13-22. [DOI: 10.2209/tdcpublication.2021-0037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Kokubu E, Kikuchi Y, Okamoto-Shibayama K, Nakamura S, Ishihara K. Crawling motility of Treponema denticola modulated by outer sheath protein. Microbiol Immunol 2021; 65:551-558. [PMID: 34499368 DOI: 10.1111/1348-0421.12940] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Revised: 08/30/2021] [Accepted: 09/06/2021] [Indexed: 11/30/2022]
Abstract
Treponema denticola, a helically shaped motile microorganism, is a major pathogen of chronic periodontitis. Major surface protein (Msp) and dentilisin are virulence factors of T. denticola that are located on the outer sheath. The motility of T. denticola is deeply involved in colonization on and invasion into the host tissue. The outer sheath is located at the interface between the environment and T. denticola, and its components may also contribute to its motility via interaction with the materials outside the cells. The study aimed to clarify whether Msp or dentilisin contributes to the motility of T. denticola on solid surfaces, termed crawling, by investigating their effects using Msp-deficient and dentilisin-deficient T. denticola strains. Motility was analyzed by measuring the colony size in agar plates and velocity was analyzed using dark-field microscopy. The colony area of the mutant strains was smaller than that of the wild-type strain. The crawling velocity of the mutant strains was lower than that of the wild-type strain, with the lowest velocity observed in the dentilisin-deficient strain. Additionally, the ratio of the crawling distance by one revolution to the protoplasmic cylinder pitch (an indicator of the crawling efficiency) in the dentilisin mutant was significantly lower than that in the wild type strain and the Msp mutant. Together, these results indicate that dentilisin facilitates the crawling-dependent surface spreading of T. denticola.
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Affiliation(s)
- Eitoyo Kokubu
- Department of Microbiology, Tokyo Dental College, Chiyoda-ku, Tokyo, Japan.,Oral Health Science Center, Tokyo Dental College, Chiyoda-ku, Tokyo, Japan
| | - Yuichiro Kikuchi
- Department of Microbiology, Tokyo Dental College, Chiyoda-ku, Tokyo, Japan.,Oral Health Science Center, Tokyo Dental College, Chiyoda-ku, Tokyo, Japan
| | - Kazuko Okamoto-Shibayama
- Department of Microbiology, Tokyo Dental College, Chiyoda-ku, Tokyo, Japan.,Oral Health Science Center, Tokyo Dental College, Chiyoda-ku, Tokyo, Japan
| | - Shuichi Nakamura
- Department of Applied Physics, Graduate School of Engineering, Tohoku University, Sendai, Miyagi, Japan
| | - Kazuyuki Ishihara
- Department of Microbiology, Tokyo Dental College, Chiyoda-ku, Tokyo, Japan.,Oral Health Science Center, Tokyo Dental College, Chiyoda-ku, Tokyo, Japan
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5
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Goetting-Minesky MP, Godovikova V, Fenno JC. Approaches to Understanding Mechanisms of Dentilisin Protease Complex Expression in Treponema denticola. Front Cell Infect Microbiol 2021; 11:668287. [PMID: 34084756 PMCID: PMC8167434 DOI: 10.3389/fcimb.2021.668287] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Accepted: 05/04/2021] [Indexed: 11/25/2022] Open
Abstract
The oral spirochete Treponema denticola is a keystone periodontal pathogen that, in association with members of a complex polymicrobial oral biofilm, contributes to tissue damage and alveolar bone loss in periodontal disease. Virulence-associated behaviors attributed to T. denticola include disruption of the host cell extracellular matrix, tissue penetration and disruption of host cell membranes accompanied by dysregulation of host immunoregulatory factors. T. denticola dentilisin is associated with several of these behaviors. Dentilisin is an outer membrane-associated complex of acylated subtilisin-family PrtP protease and two other lipoproteins, PrcB and PrcA, that are unique to oral spirochetes. Dentilisin is encoded in a single operon consisting of prcB-prcA-prtP. We employ multiple approaches to study mechanisms of dentilisin assembly and PrtP protease activity. To determine the role of each protein in the protease complex, we have made targeted mutations throughout the protease locus, including polar and nonpolar mutations in each gene (prcB, prcA, prtP) and deletions of specific PrtP domains, including single base mutagenesis of key PrtP residues. These will facilitate distinguishing between host cell responses to dentilisin protease activity and its acyl groups. The boundaries of the divergent promoter region and the relationship between dentilisin and the adjacent iron transport operon are being resolved by incremental deletions in the sequence immediately 5’ to the protease locus. Comparison of the predicted three-dimensional structure of PrtP to that of other subtilisin-like proteases shows a unique PrtP C-terminal domain of approximately 250 residues. A survey of global gene expression in the presence or absence of protease gene expression reveals potential links between dentilisin and iron uptake and homeostasis in T. denticola. Understanding the mechanisms of dentilisin transport, assembly and activity of this unique protease complex may lead to more effective prophylactic or therapeutic treatments for periodontal disease.
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Affiliation(s)
- M Paula Goetting-Minesky
- Department of Biologic and Materials Sciences & Prosthodontics, School of Dentistry, University of Michigan, Ann Arbor, MI, United States
| | - Valentina Godovikova
- Department of Biologic and Materials Sciences & Prosthodontics, School of Dentistry, University of Michigan, Ann Arbor, MI, United States
| | - J Christopher Fenno
- Department of Biologic and Materials Sciences & Prosthodontics, School of Dentistry, University of Michigan, Ann Arbor, MI, United States
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Abstract
Treponema denticola is a potent periodontal pathogen that forms a red complex with Porphyromonas gingivalis and Tannerella forsythia. It has many virulence factors, yet there are only a few reports detailing these factors. Among them, dentilisin is a well-documented surface protease. Dentilisin is reported to be involved in nutrient uptake, bacterial coaggregation, complement activation, evasion of the host immune system, inhibition of the hemostasis system, and cell invasion as a result of its action, in addition to its original proteolysis function. Therefore, characterization of dentilisin, and clarifying the relationship between T. denticola and the onset of periodontal disease will be important to better understanding this disease. In this chapter, we explain the methods for analysis of dentilisin activity and pathogenicity.
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Affiliation(s)
- Yuichiro Kikuchi
- Department of Microbiology, Tokyo Dental College, Tokyo, Japan
- Oral Health Science Center, Tokyo Dental College, Tokyo, Japan
| | - Kazuyuki Ishihara
- Department of Microbiology, Tokyo Dental College, Tokyo, Japan.
- Oral Health Science Center, Tokyo Dental College, Tokyo, Japan.
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7
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Arai Y, Kikuchi Y, Okamoto-Shibayama K, Kokubu E, Shintani S, Ishihara K. Investigation of the potential regulator proteins associated with the expression of major surface protein and dentilisin in Treponema denticola. J Oral Microbiol 2020; 12:1829404. [PMID: 33149843 PMCID: PMC7586716 DOI: 10.1080/20002297.2020.1829404] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022] Open
Abstract
ObjectiveTreponema denticola is involved in ‘chronic’ periodontitis pathogenesis. The mechanism underlying the regulation of the expression of its virulence factors, such as major surface protein (Msp) and prolyl-phenylalanine specific protease (dentilisin) is yet to be clarified. We determined the gene expression profiles of Msp- and dentilisin-deficient mutants of T. denticola to identify the regulation network of gene expression concomitant with the inactivation of these virulence genes. Methods Gene expression profiles of T. denticola ATCC 35405 (wild type), dentilisin-deficient mutant K1, and msp-deficient mutant DMSP3 were determined using DNA microarray analysis and quantitative real-time reverse transcription PCR (qRT-PCR). Msp and dentilisin protein levels were determined by immunoblotting and proteolytic activity assays. Results In addition to several differentially expressed genes, dentilisin expression was reduced in DMSP3; msp expression was significantly reduced in K1 (p < 0.05), both at the gene and protein levels. To identify the regulatory system involved, the expression levels of the potential regulators whose expression showed changes in the mutants were evaluated using qRT-PCR. Transcriptional regulators TDE_0127 and TDE_0814 were upregulated in K1, and the potential repressor, TDE_0344, was elevated in DMSP3. Conclusions Dentilisin and Msp expression were interrelated, and gene expression regulators, such as TDE_0127, may be involved in their regulation.
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Affiliation(s)
- Yuki Arai
- Department of Pediatric Dentistry, Tokyo Dental College, Tokyo, Japan
| | | | | | - Eitoyo Kokubu
- Department of Microbiology, Tokyo Dental College, Tokyo, Japan
| | - Seikou Shintani
- Department of Pediatric Dentistry, Tokyo Dental College, Tokyo, Japan
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8
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Silbergleit M, Vasquez AA, Miller CJ, Sun J, Kato I. Oral and intestinal bacterial exotoxins: Potential linked to carcinogenesis. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2020; 171:131-193. [PMID: 32475520 DOI: 10.1016/bs.pmbts.2020.02.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Growing evidence suggests that imbalances in resident microbes (dysbiosis) can promote chronic inflammation, immune-subversion, and production of carcinogenic metabolites, thus leading to neoplasia. Yet, evidence to support a direct link of individual bacteria species to human sporadic cancer is still limited. This chapter focuses on several emerging bacterial toxins that have recently been characterized for their potential oncogenic properties toward human orodigestive cancer and the presence of which in human tissue samples has been documented. These include cytolethal distending toxins produced by various members of gamma and epsilon Proteobacteria, Dentilisin from mammalian oral Treponema, Pasteurella multocida toxin, two Fusobacterial toxins, FadA and Fap2, Bacteroides fragilis toxin, colibactin, cytotoxic necrotizing factors and α-hemolysin from Escherichia coli, and Salmonella enterica AvrA. It was clear that these bacterial toxins have biological activities to induce several hallmarks of cancer. Some toxins directly interact with DNA or chromosomes leading to their breakdowns, causing mutations and genome instability, and others modulate cell proliferation, replication and death and facilitate immune evasion and tumor invasion, prying specific oncogene and tumor suppressor pathways, such as p53 and β-catenin/Wnt. In addition, most bacterial toxins control tumor-promoting inflammation in complex and diverse mechanisms. Despite growing laboratory evidence to support oncogenic potential of selected bacterial toxins, we need more direct evidence from human studies and mechanistic data from physiologically relevant experimental animal models, which can reflect chronic infection in vivo, as well as take bacterial-bacterial interactions among microbiome into consideration.
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Affiliation(s)
| | - Adrian A Vasquez
- Department of Civil and Environmental Engineering, Wayne State University, Healthy Urban Waters, Detroit, MI, United States
| | - Carol J Miller
- Department of Civil and Environmental Engineering, Wayne State University, Healthy Urban Waters, Detroit, MI, United States
| | - Jun Sun
- Department of Medicine, College of Medicine, University of Illinois at Chicago, Chicago, IL, United States
| | - Ikuko Kato
- Department of Oncology, Wayne State University School of Medicine, Detroit, MI, United States; Department of Pathology, Wayne State University School of Medicine, Detroit, MI, United States.
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9
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Chu L, Wu Y, Xu X, Phillips L, Kolodrubetz D. Glutathione catabolism by Treponema denticola impacts its pathogenic potential. Anaerobe 2020; 62:102170. [PMID: 32044394 PMCID: PMC7153967 DOI: 10.1016/j.anaerobe.2020.102170] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 01/14/2020] [Accepted: 02/04/2020] [Indexed: 12/28/2022]
Abstract
Treponema denticola is a spirochete that is etiologic for periodontal diseases. This bacterium is one of two periodontal pathogens that have been shown to have a complete three step enzymatic pathway (GTSP) that catabolizes glutathione to H2S. This pathway may contribute to the tissue pathology seen in periodontitis since diseased periodontal pockets have lower glutathione levels than healthy sites with a concomitant increase in H2S concentration. In order to be able to demonstrate that glutathione catabolism by the GTSP is critical for the pathogenic potential of T. denticola, allelic replacement mutagenesis was used to make a deletion mutant (Δggt) in the gene encoding the first enzyme in the GTSP. The mutant cannot produce H2S from glutathione since it lacks gamma-glutamyltransferase (GGT) activity. The hemolytic and hemoxidation activities of wild type T. denticola plus glutathione are reduced to background levels with the Δggt mutant and the mutant has lost the ability to grow aerobically when incubated with glutathione. The Δggt bacteria with glutathione cause less cell death in human gingival fibroblasts (hGFs) in vitro than do wild type T. denticola and the levels of hGF death correlate with the amounts of H2S produced. Importantly, the mutant spirochetes plus glutathione make significantly smaller lesions than wild type bacteria plus glutathione in a mouse back lesion model that assesses soft tissue destruction, a major symptom of periodontal diseases. Our results are the first to prove that T. denticola thiol-compound catabolism by its gamma-glutamyltransferase can play a significant role in the in the types of host tissue damage seen in periodontitis.
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Affiliation(s)
- Lianrui Chu
- Department of Developmental Dentistry, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Yimin Wu
- Department of Developmental Dentistry, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Xiaoping Xu
- Department of Periodontics, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Linda Phillips
- Department of Microbiology, Immunology and Molecular Genetics, UT Health San Antonio, 7703 Floyd Curl Drive, San Antonio, TX, 78229, USA
| | - David Kolodrubetz
- Department of Microbiology, Immunology and Molecular Genetics, UT Health San Antonio, 7703 Floyd Curl Drive, San Antonio, TX, 78229, USA.
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Ng HM, Slakeski N, Butler CA, Veith PD, Chen YY, Liu SW, Hoffmann B, Dashper SG, Reynolds EC. The Role of Treponema denticola Motility in Synergistic Biofilm Formation With Porphyromonas gingivalis. Front Cell Infect Microbiol 2019; 9:432. [PMID: 31921707 PMCID: PMC6930189 DOI: 10.3389/fcimb.2019.00432] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Accepted: 12/04/2019] [Indexed: 12/29/2022] Open
Abstract
Chronic periodontitis has a polymicrobial biofilm etiology and interactions between key oral bacterial species, such as Porphyromonas gingivalis and Treponema denticola contribute to disease progression. P. gingivalis and T. denticola are co-localized in subgingival plaque and have been previously shown to exhibit strong synergy in growth, biofilm formation and virulence in an animal model of disease. The motility of T. denticola, although not considered as a classic virulence factor, may be involved in synergistic biofilm development between P. gingivalis and T. denticola. We determined the role of T. denticola motility in polymicrobial biofilm development using an optimized transformation protocol to produce two T. denticola mutants targeting the motility machinery. These deletion mutants were non-motile and lacked the gene encoding the flagellar hook protein of the periplasmic flagella (ΔflgE) or a component of the stator motor that drives the flagella (ΔmotB). The specificity of these gene deletions was determined by whole genome sequencing. Quantitative proteomic analyses of mutant strains revealed that the specific inactivation of the motility-associated gene, motB, had effects beyond motility. There were 64 and 326 proteins that changed in abundance in the ΔflgE and ΔmotB mutants, respectively. In the ΔflgE mutant, motility-associated proteins showed the most significant change in abundance confirming the phenotype change for the mutant was related to motility. However, the inactivation of motB as well as stopping motility also upregulated cellular stress responses in the mutant indicating pleiotropic effects of the mutation. T. denticola wild-type and P. gingivalis displayed synergistic biofilm development with a 2-fold higher biomass of the dual-species biofilms than the sum of the monospecies biofilms. Inactivation of T. denticola flgE and motB reduced this synergy. A 5-fold reduction in dual-species biofilm biomass was found with the motility-specific ΔflgE mutant suggesting that T. denticola periplasmic flagella are essential in synergistic biofilm formation with P. gingivalis.
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Affiliation(s)
- Hong Min Ng
- Oral Health Cooperative Research Centre, Melbourne Dental School, Bio21 Institute, The University of Melbourne, Melbourne, VIC, Australia
| | - Nada Slakeski
- Oral Health Cooperative Research Centre, Melbourne Dental School, Bio21 Institute, The University of Melbourne, Melbourne, VIC, Australia
| | - Catherine A Butler
- Oral Health Cooperative Research Centre, Melbourne Dental School, Bio21 Institute, The University of Melbourne, Melbourne, VIC, Australia
| | - Paul D Veith
- Oral Health Cooperative Research Centre, Melbourne Dental School, Bio21 Institute, The University of Melbourne, Melbourne, VIC, Australia
| | - Yu-Yen Chen
- Oral Health Cooperative Research Centre, Melbourne Dental School, Bio21 Institute, The University of Melbourne, Melbourne, VIC, Australia
| | - Sze Wei Liu
- Oral Health Cooperative Research Centre, Melbourne Dental School, Bio21 Institute, The University of Melbourne, Melbourne, VIC, Australia
| | - Brigitte Hoffmann
- Oral Health Cooperative Research Centre, Melbourne Dental School, Bio21 Institute, The University of Melbourne, Melbourne, VIC, Australia
| | - Stuart G Dashper
- Oral Health Cooperative Research Centre, Melbourne Dental School, Bio21 Institute, The University of Melbourne, Melbourne, VIC, Australia
| | - Eric C Reynolds
- Oral Health Cooperative Research Centre, Melbourne Dental School, Bio21 Institute, The University of Melbourne, Melbourne, VIC, Australia
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Kikuchi Y, Kimizuka R, Kato T, Okuda K, Kokubu E, Ishihara K. Treponema denticola Induces Epithelial Barrier Dysfunction in Polarized Epithelial Cells. THE BULLETIN OF TOKYO DENTAL COLLEGE 2018; 59:265-275. [PMID: 30333370 DOI: 10.2209/tdcpublication.2017-0052] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Treponema denticola, an anaerobic spirochete found mainly in the oral cavity, is associated with periodontal disease and has a variety of virulence factors. Although in vitro studies have shown that T. denticola is able to penetrate epithelial cell monolayers, its effect on the epithelial barrier junction is not known. Human gingival epithelial cells are closely associated with adjacent membranes, forming barriers in the presence of tight junction proteins, including zonula occludens-1 (ZO-1), claudin-1, and occludin. Tight junction proteins are also expressed by Madin-Darby canine kidney (MDCK) cells in culture. In this study, the MDCK cell profile was investigated following infection with T. denticola (ATCC 35405) wild-type, as well as with its dentilisin-deficient mutant, K1. Basolateral exposure of MDCK cell monolayers to T. denticola at a multiplicity of infection (MOI) of 104 resulted in a decrease in transepithelial electrical resistance (TER). Transepithelial electrical resistance in MDCK cell monolayers also decreased following apical exposure to T. denticola (MOI=104), although this took longer with basolateral exposure. The effect on the TER was time-dependent and required the presence of live bacteria. Meanwhile, MDCK cell viability showed a decrease with either basolateral or apical exposure. Immunofluorescence analysis demonstrated decreases in the amounts of immunoreactive ZO-1 and claudin-1 in association with disruption of cell-cell junctions in MDCK cells exposed apically or basolaterally to T. denticola. Western blot analysis demonstrated degradation of ZO-1 and claudin-1 in culture lysates derived from T. denticola-exposed MDCK cells, suggesting a bacteria-induced protease capable of cleaving these tight junction proteins.
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Affiliation(s)
- Yuichiro Kikuchi
- Department of Microbiology, Tokyo Dental College.,Oral Health Science Center, Tokyo Dental College
| | | | - Tetsuo Kato
- Laboratory of Chemistry, Tokyo Dental College
| | | | - Eitoyo Kokubu
- Department of Microbiology, Tokyo Dental College.,Oral Health Science Center, Tokyo Dental College
| | - Kazuyuki Ishihara
- Department of Microbiology, Tokyo Dental College.,Oral Health Science Center, Tokyo Dental College
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12
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Kokubu E, Inoue T, Ishihara K. Response of epithelial cells infected by Treponema denticola. Oral Dis 2018; 24:14-18. [PMID: 29480639 DOI: 10.1111/odi.12794] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Revised: 09/21/2017] [Accepted: 09/22/2017] [Indexed: 12/16/2022]
Abstract
OBJECTIVE In the gingival crevice, the interaction between epithelial cells and periodontopathic bacteria is important for the development of periodontitis. Treponema denticola is a major pathogen of chronic periodontitis and possesses several virulence factors, such as major surface protein (Msp) and prolyl-phenylalanine-specific protease (dentilisin). Here, we investigated the behaviours of epithelial cells infected with T. denticola by measuring the expression of interleukin (IL)-1β, IL-6, β defensin 2 (BD-2) and heat-shock protein 70 (HSP70). METHODS Epithelial cells were infected with T. denticola wild-type strain, Msp-deficient mutant or dentilisin-deficient mutant, and the expression levels of the above targets were analysed by polymerase chain reaction. RESULTS Infection with T. denticola wild-type strain and mutants induced the production of IL-6 and HSP70. The level of BD-2 induced by T. denticola wild-type strain at 24 hr was significantly higher than that of the dentilisin-deficient mutant. The level of IL-1β mRNA in the wild-type strain and dentilisin-deficient mutant was slightly lower than that in the uninfected control. CONCLUSION These results suggest that the levels of BD-2 were affected by Msp and dentilisin. This effect may contribute to the disruption of the response of epithelial cells to eradicate T. denticola.
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Affiliation(s)
- E Kokubu
- Department of Microbiology, Tokyo Dental College, Tokyo, Japan.,Oral Health Science Center, Tokyo Dental College, Tokyo, Japan
| | - T Inoue
- Oral Health Science Center, Tokyo Dental College, Tokyo, Japan.,Department of Clinical Pathophysiology, Tokyo Dental College, Tokyo, Japan
| | - K Ishihara
- Department of Microbiology, Tokyo Dental College, Tokyo, Japan.,Oral Health Science Center, Tokyo Dental College, Tokyo, Japan
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13
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Asai T, Okamoto-Shibayama K, Kikuchi Y, Ishihara K. Characterization of a novel potential peptide import system in Treponema denticola. Microb Pathog 2018; 123:467-472. [PMID: 30076984 DOI: 10.1016/j.micpath.2018.07.045] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2018] [Revised: 07/31/2018] [Accepted: 07/31/2018] [Indexed: 01/27/2023]
Abstract
Treponema denticola is a major etiologic agent of chronic periodontitis. On the outer sheath of T. denticola, several proteins, such as the major outer sheath protein and dentilisin were detected, and among them, a 95 kDa protein which has not yet been characterized. The aim of this study was to characterize the function of this 95 kDa protein containing gene cluster. A gene encoding this 95 kDa protein (TDE_1072) of T. denticola was inactivated by homologous recombination. We compared growth curves between the TDE_1072 mutant and wild-type strains as well as differences in gene expression by DNA microarray analysis. Differential expression of genes identified by microarray analysis was confirmed by quantitative reverse transcription-polymerase chain reaction. The proteins encoded by TDE_1072, TDE_1073, TDE_1074, TDE_1075, and TDE_1076 shared respective similarities to the substrate-binding domain (DppA) of an ABC-type dipeptide/oligopeptide/nickel transport system, and to the permease components (DppB and DppC) and ATPase components (DppD and DppF) of an ABC-type dipeptide/oligopeptide/nickel transport system. Inactivation of dppA attenuated the growth of T. denticola and dppA-dppF were co-transcribed. In contrast, expression of oppB-oppF was up-regulated in the mutant. Our findings indicate that TDE_1072 may be a potential periplasmic solute binding protein encoded by dppA that is involved in the organization of a peptide uptake system with dppB-dppF.
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Affiliation(s)
- Tomohiro Asai
- Oral Health Science Center, Tokyo Dental College, 2-9-18 Kanda-Misakicho, Chiyoda-ku, Tokyo 101-0061, Japan; Department of Endodontics, Tokyo Dental College, 2-9-18 Kanda-Misakicho, Chiyoda-ku, Tokyo 101-0061, Japan
| | - Kazuko Okamoto-Shibayama
- Oral Health Science Center, Tokyo Dental College, 2-9-18 Kanda-Misakicho, Chiyoda-ku, Tokyo 101-0061, Japan; Department of Microbiology, Tokyo Dental College, 2-1-14 Kanda-Misakicho, Chiyoda-ku, Tokyo 101-0061, Japan
| | - Yuichiro Kikuchi
- Oral Health Science Center, Tokyo Dental College, 2-9-18 Kanda-Misakicho, Chiyoda-ku, Tokyo 101-0061, Japan; Department of Microbiology, Tokyo Dental College, 2-1-14 Kanda-Misakicho, Chiyoda-ku, Tokyo 101-0061, Japan
| | - Kazuyuki Ishihara
- Oral Health Science Center, Tokyo Dental College, 2-9-18 Kanda-Misakicho, Chiyoda-ku, Tokyo 101-0061, Japan; Department of Microbiology, Tokyo Dental College, 2-1-14 Kanda-Misakicho, Chiyoda-ku, Tokyo 101-0061, Japan.
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14
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Yoshikawa K, Kikuchi Y, Kokubu E, Imamura K, Saito A, Ishihara K. Identification of a specific domain of Porphyromonas gingivalis Hgp44 responsible for adhesion to Treponema denticola. Pathog Dis 2018; 76:4995196. [PMID: 29771309 DOI: 10.1093/femspd/fty047] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Accepted: 05/09/2018] [Indexed: 11/12/2022] Open
Abstract
Interaction between two periodontal pathogens, Porphyromonas gingivalis and Treponema denticola, contributes to plaque biofilm formation. Porphyromonas gingivalis forms aggregates with T. denticola through its adhesion/hemagglutinin domain (Hgp44). In this study, we investigated the specific domain of P. gingivalis Hgp44 responsible for adhesion to T. denticola using expression vectors harboring P. gingivalis Hgp44 DNA sequences encoding amino acid residues 1-419. Six plasmids harboring fragments in this region were generated by PCR amplification and self-ligation, and recombinant proteins r-Hgp44 (residues 1-419), r-Hgp441 (residues 1-124), r-Hgp442 (1-199), r-Hgp443 (1-316), r-Hgp444 (199-419), r-Hgp445 (124-198) and r-Hgp446 (199-316) were produced, as confirmed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting. r-Hgp44, r-Hgp443 and r-Hgp446 showed greater adhesion to T. denticola sonicates than the control, as determined by enzyme-linked immunosorbent assay. r-Hgp446 reduced the coaggregation of P. gingivalis and T. denticola. Scanning electron and confocal laser scanning microscopy analyses revealed that r-Hgp446 reduced dual-species biofilm formation. Our results indicate that residues 199-316 of P. gingivalis Hgp44 are mainly responsible for adhesion to T. denticola; inhibiting this domain could potentially disrupt periodontopathic biofilm formation and maturation.
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Affiliation(s)
- Kouki Yoshikawa
- Department of Periodontology, Tokyo Dental College, Tokyo 101-0061, Japan
| | - Yuichiro Kikuchi
- Department of Microbiology, Tokyo Dental College, Tokyo 101-0061, Japan.,Oral Health Science Center, Tokyo Dental College, Tokyo 101-0061, Japan
| | - Eitoyo Kokubu
- Department of Microbiology, Tokyo Dental College, Tokyo 101-0061, Japan.,Oral Health Science Center, Tokyo Dental College, Tokyo 101-0061, Japan
| | - Kentaro Imamura
- Department of Periodontology, Tokyo Dental College, Tokyo 101-0061, Japan
| | - Atsushi Saito
- Department of Periodontology, Tokyo Dental College, Tokyo 101-0061, Japan.,Oral Health Science Center, Tokyo Dental College, Tokyo 101-0061, Japan
| | - Kazuyuki Ishihara
- Department of Microbiology, Tokyo Dental College, Tokyo 101-0061, Japan.,Oral Health Science Center, Tokyo Dental College, Tokyo 101-0061, Japan
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15
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Gene Regulation, Two Component Regulatory Systems, and Adaptive Responses in Treponema Denticola. Curr Top Microbiol Immunol 2017; 415:39-62. [PMID: 29026924 DOI: 10.1007/82_2017_66] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The oral microbiome consists of a remarkably diverse group of 500-700 bacterial species. The microbial etiology of periodontal disease is similarly complex. Of the ~400 bacterial species identified in subgingival plaque, at least 50 belong to the genus Treponema. As periodontal disease develops and progresses, T. denticola transitions from a low to high abundance species in the subgingival crevice. Changes in the overall composition of the bacterial population trigger significant changes in the local physical, immunological and physiochemical conditions. For T. denticola to thrive in periodontal pockets, it must be nimble and adapt to rapidly changing environmental conditions. The purpose of this chapter is to review the current understanding of the molecular basis of these essential adaptive responses, with a focus on the role of two component regulatory systems with global regulatory potential.
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16
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Tanaka-Kumazawa K, Kikuchi Y, Sano-Kokubun Y, Shintani S, Yakushiji M, Kuramitsu HK, Ishihara K. Characterization of a potential ABC-type bacteriocin exporter protein from Treponema denticola. BMC Oral Health 2016; 17:18. [PMID: 27422166 PMCID: PMC4947327 DOI: 10.1186/s12903-016-0243-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Accepted: 07/02/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Treponema denticola is strongly associated with the development of periodontal disease. Both synergistic and antagonistic effects are observed among bacterial species in the process of biofilm formation. Bacteriocin-related genes have not yet been fully characterized in periodontopathic bacteria. The aim of this study was to detect and characterize bacteriocin-associated proteins in T. denticola. METHODS The whole genome sequence of T. denticola ATCC 35405 was screened with a Streptococcus mutans bacteriocin immunity protein (ImmA/Bip) sequence. The prevalence of homologous genes in T. denticola strains was then investigated by Southern blotting. Expression of the genes was evaluated by qRT-PCR. RESULTS In the genome sequence of T. denticola, an amino acid sequence coded by the open reading frame TDE_0719 showed 26 % identity with the S. mutans ImmA. Furthermore, two protein sequences encoded by TDE_0425 and TDE_2431 in T. denticola ATCC 35405 showed ~40 % identity with that coded by TDE_0719. Therefore, TDE_0425, TDE_0719, and TDE_2431 were designated as tepA1, A2, and A3, respectively. Open reading frames showing similarity to the HlyD family of secretion proteins were detected downstream of tepA1, A2, and A3. They were designated as tepB1, B2, and B3, respectively. A gene harboring a bacteriocin-like signal sequence was detected upstream of tepA1. The prevalence of tepA1 and A2 differed among Treponema species. Susceptibility to chloramphenicol and ofloxacin was slightly decreased in a tepA2 mutant while that to kanamycin was increased. Expression of tepA3-B3 was increased in the tepA2 mutant. CONCLUSION These results indicate that T. denticola ATCC 35405 has three potential bacteriocin export proteins and that the presence of these genes differs among the Treponema strains. TepA3-B3 of the corresponding proteins may be involved in resistance to chloramphenicol.
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Affiliation(s)
- Kimiko Tanaka-Kumazawa
- Department of Pediatric Dentistry, Tokyo Dental College, 2-9-18 Misaki-cho, Chiyoda-ku, Tokyo, 101-0061, Japan
| | - Yuichiro Kikuchi
- Department of Microbiology, Tokyo Dental College, 2-9-18 Misaki-cho, Chiyoda-ku, Tokyo, 101-0061, Japan.,Oral Health Science Center, Tokyo Dental College, 2-9-18 Misaki-cho, Chiyoda-ku, Tokyo, 101-0061, Japan
| | - Yumiko Sano-Kokubun
- Department of Pediatric Dentistry, Tokyo Dental College, 2-9-18 Misaki-cho, Chiyoda-ku, Tokyo, 101-0061, Japan
| | - Seikou Shintani
- Department of Pediatric Dentistry, Tokyo Dental College, 2-9-18 Misaki-cho, Chiyoda-ku, Tokyo, 101-0061, Japan
| | - Masashi Yakushiji
- Department of Pediatric Dentistry, Tokyo Dental College, 2-9-18 Misaki-cho, Chiyoda-ku, Tokyo, 101-0061, Japan
| | - Howard K Kuramitsu
- Department of Oral Biology, State University of New York, Buffalo, NY, USA
| | - Kazuyuki Ishihara
- Department of Microbiology, Tokyo Dental College, 2-9-18 Misaki-cho, Chiyoda-ku, Tokyo, 101-0061, Japan. .,Oral Health Science Center, Tokyo Dental College, 2-9-18 Misaki-cho, Chiyoda-ku, Tokyo, 101-0061, Japan.
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17
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Inagaki S, Kimizuka R, Kokubu E, Saito A, Ishihara K. Treponema denticola invasion into human gingival epithelial cells. Microb Pathog 2016; 94:104-11. [PMID: 26806000 DOI: 10.1016/j.micpath.2016.01.010] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Revised: 01/08/2016] [Accepted: 01/12/2016] [Indexed: 02/06/2023]
Abstract
Host cell invasion is important for periodontal pathogens in evading host defenses and spreading into deeper areas of the periodontal tissue. Treponema denticola has been implicated in a number of potentially pathogenic processes, including periodontal tissue penetration. Here we tested the ability of T. denticola strains to invade human gingival epithelial cells (HGEC). After 2 h infection, intracellular location of T. denticola cells was confirmed by confocal laser scanning microscopy (CLSM). Results from an antibiotic protection assay following [(3)H]uridine labeling indicated that invasion efficiency reached a maximum at 2 h after infection. Internalized T. denticola cells were still observed in HGEC at 24 h by CLSM. A dentilisin deficient mutant exhibited significantly decreased invasion (p < 0.05) compared with the wild-type strain. In inhibition assays, phenylmethylsulfonyl fluoride and metabolic inhibitors such as methyl-β-cyclodextrin and staurosporine significantly reduced T. denticola invasion. Under CLSM, T. denticola colocalized with GM-1 ganglioside-containing membrane microdomains in a cholesterol-dependent manner. These results indicated that T. denticola has the ability to invade into and survive within HGECs. Dentilisin activity of T. denticola and lipid rafts on HGEC appear to play important roles in this process.
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Affiliation(s)
- Satoru Inagaki
- Oral Health Science Center, Tokyo Dental College, 2-9-18 Misaki-cho, Chiyoda-ku, Tokyo 101-0064, Japan; Department of Microbiology, Tokyo Dental College, 2-1-14 Misaki-cho, Chiyoda-ku, Tokyo 101-0061, Japan
| | - Ryuta Kimizuka
- Oral Health Science Center, Tokyo Dental College, 2-9-18 Misaki-cho, Chiyoda-ku, Tokyo 101-0064, Japan; Department of Microbiology, Tokyo Dental College, 2-1-14 Misaki-cho, Chiyoda-ku, Tokyo 101-0061, Japan
| | - Eitoyo Kokubu
- Oral Health Science Center, Tokyo Dental College, 2-9-18 Misaki-cho, Chiyoda-ku, Tokyo 101-0064, Japan; Department of Microbiology, Tokyo Dental College, 2-1-14 Misaki-cho, Chiyoda-ku, Tokyo 101-0061, Japan
| | - Atsushi Saito
- Oral Health Science Center, Tokyo Dental College, 2-9-18 Misaki-cho, Chiyoda-ku, Tokyo 101-0064, Japan; Department of Periodontology, Tokyo Dental College, 2-9-18 Misaki-cho, Chiyoda-ku, Tokyo 101-0061, Japan
| | - Kazuyuki Ishihara
- Oral Health Science Center, Tokyo Dental College, 2-9-18 Misaki-cho, Chiyoda-ku, Tokyo 101-0064, Japan; Department of Microbiology, Tokyo Dental College, 2-1-14 Misaki-cho, Chiyoda-ku, Tokyo 101-0061, Japan.
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18
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Sano Y, Okamoto-Shibayama K, Tanaka K, Ito R, Shintani S, Yakushiji M, Ishihara K. Dentilisin involvement in coaggregation between Treponema denticola and Tannerella forsythia. Anaerobe 2014; 30:45-50. [DOI: 10.1016/j.anaerobe.2014.08.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2014] [Revised: 08/11/2014] [Accepted: 08/13/2014] [Indexed: 12/11/2022]
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19
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Abiko Y, Nagano K, Yoshida Y, Yoshimura F. Characterization of Treponema denticola mutants defective in the major antigenic proteins, Msp and TmpC. PLoS One 2014; 9:e113565. [PMID: 25401769 PMCID: PMC4234677 DOI: 10.1371/journal.pone.0113565] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Accepted: 10/27/2014] [Indexed: 12/28/2022] Open
Abstract
Treponema denticola, a gram-negative and anaerobic spirochete, is associated with advancing severity of chronic periodontitis. In this study, we confirmed that two major antigenic proteinswere Msp and TmpC, and examined their physiological and pathological roles using gene-deletion mutants. Msp formed a large complex that localized to the outer membrane, while TmpC existed as a monomer and largely localized to the inner membrane. However, TmpC was also detected in the outer membrane fraction, but its cell-surface exposure was not detected. Msp defects increased cell-surface hydrophobicity and secretion of TNF-α from macrophage-like cells, whereas TmpC defects decreased autoagglutination and chymotrypsin-like protease activities. Both mutants adhered to gingival epithelial cells similarly to the wild-type and showed slightly decreased motility. In addition, in Msp-defective mutants, the TDE1072 protein, which is a major membrane protein, was abolished; therefore, phenotypic changes in the mutant can be, at least in part, attributed to the loss of the TDE1072 protein. Thus, the major antigenic proteins, Msp and TmpC, have significant and diverse impacts on the characteristics of T. denticola, especially cell surface properties.
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Affiliation(s)
- Yuki Abiko
- Department of Microbiology, School of Dentistry, Aichi Gakuin University Nagoya, Aichi, Japan
| | - Keiji Nagano
- Department of Microbiology, School of Dentistry, Aichi Gakuin University Nagoya, Aichi, Japan
| | - Yasuo Yoshida
- Department of Microbiology, School of Dentistry, Aichi Gakuin University Nagoya, Aichi, Japan
| | - Fuminobu Yoshimura
- Department of Microbiology, School of Dentistry, Aichi Gakuin University Nagoya, Aichi, Japan
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20
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Miller DP, McDowell JV, Bell JK, Goetting-Minesky MP, Fenno JC, Marconi RT. Analysis of the complement sensitivity of oral treponemes and the potential influence of FH binding, FH cleavage and dentilisin activity on the pathogenesis of periodontal disease. Mol Oral Microbiol 2014; 29:194-207. [PMID: 24815960 DOI: 10.1111/omi.12054] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/04/2014] [Indexed: 12/28/2022]
Abstract
Treponema denticola, a periopathogen, evades complement-mediated killing by binding the negative complement regulatory protein factor H (FH) to its surface via the FhbB protein. Paradoxically, bound FH is cleaved by T. denticola's dentilisin protease, a process hypothesized to trigger localized dysregulation of complement activation in periodontal pockets. The ability of other oral treponemes to evade complement-mediated killing and bind and cleave FH has not been assessed. In this report, we demonstrate that representative isolates of Treponema socranskii, Treponema medium, Treponema pectinovorum and Treponema maltophilum are also serum resistant, whereas Treponema vincentii and Treponema amylovorum are serum sensitive. Although T. denticola's ability to evade complement-mediated killing is strictly dependent on FH binding, other serum-resistant treponemal species lack FhbB and do not bind FH, indicating an FH-independent mechanism of complement evasion. To assess the influence of FhbB sequence variation on FH binding and cleavage by T. denticola, fhbB sequences were determined for 30 isolates. Three distinct phyletic types were identified. All T. denticola strains bound FH and were serum resistant, but differences in binding kinetics, dentilisin activity and FH cleavage ability were observed. Based on these analyses, we hypothesize that the composition of the T. denticola population is a determining factor that influences the progression and severity of periodontal disease.
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Affiliation(s)
- D P Miller
- Department of Microbiology and Immunology, Medical College of Virginia, Virginia Commonwealth University, Richmond, VA, USA
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21
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Abiko Y, Nagano K, Yoshida Y, Yoshimura F. Major membrane protein TDE2508 regulates adhesive potency in Treponema denticola. PLoS One 2014; 9:e89051. [PMID: 24586498 PMCID: PMC3931704 DOI: 10.1371/journal.pone.0089051] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2013] [Accepted: 01/13/2014] [Indexed: 12/13/2022] Open
Abstract
The cultivation and genetic manipulation of Treponema denticola, a Gram-negative oral spirochaeta associated with periodontal diseases, is still challenging. In this study, we formulated a simple medium based on a commercially available one, and established a transformation method with high efficiency. We then analyzed proteins in a membrane fraction in T. denticola and identified 16 major membrane-associated proteins, and characterized one of them, TDE2508, whose biological function was not yet known. Although this protein, which exhibited a complex conformation, was presumably localized in the outer membrane, we did not find conclusive evidence that it was exposed on the cell surface. Intriguingly, a TDE2508-deficient mutant exhibited significantly increased biofilm formation and adherent activity on human gingival epithelial cells. However, the protein deficiency did not alter autoaggregation, coaggregation with Porphyromonas gingivalis, hemagglutination, cell surface hydrophobicity, motility, or expression of Msp which was reported to be an adherent molecule in this bacteria. In conclusion, the major membrane protein TDE2508 regulates biofilm formation and the adhesive potency of T. denticola, although the underlying mechanism remains unclear.
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Affiliation(s)
- Yuki Abiko
- Department of Microbiology, School of Dentistry, Aichi Gakuin University, Kusumoto-cho, Chikusa-ku, Nagoya, Aichi, Japan
| | - Keiji Nagano
- Department of Microbiology, School of Dentistry, Aichi Gakuin University, Kusumoto-cho, Chikusa-ku, Nagoya, Aichi, Japan
- * E-mail:
| | - Yasuo Yoshida
- Department of Microbiology, School of Dentistry, Aichi Gakuin University, Kusumoto-cho, Chikusa-ku, Nagoya, Aichi, Japan
| | - Fuminobu Yoshimura
- Department of Microbiology, School of Dentistry, Aichi Gakuin University, Kusumoto-cho, Chikusa-ku, Nagoya, Aichi, Japan
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22
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Mechanisms of IL-8 suppression by Treponema denticola in gingival epithelial cells. Immunol Cell Biol 2013; 92:139-47. [PMID: 24296811 DOI: 10.1038/icb.2013.80] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2013] [Revised: 10/04/2013] [Accepted: 10/15/2013] [Indexed: 01/05/2023]
Abstract
The purpose of this study was to investigate the mechanism(s) of interleukin (IL)-8 suppression by Treponema denticola, one of the major periodontal pathogens, in gingival epithelial cells. Immortalized human gingival epithelial HOK-16B cells were infected with wild-type (WT), dentilisin-deficient (K1) or flagellin-deficient (flgE) T. denticola in the presence or absence of 2% human serum for 24 h. The levels of IL-8 expression were measured with real-time reverse transcription PCR and ELISA. In the absence of human serum, the WT and flgE, but not K1, substantially reduced not only the levels of IL-8 protein but also of IL-8 mRNA. Such downregulation of IL-8 mRNA was independent of bacterial invasion. Degradation of cytokine mixture by the WT, K1 and flgE revealed dentilisin-dependent preferential degradation of tumor necrosis factor (TNF)-α, an IL-8-inducing cytokine. WT and flgE significantly decreased the levels of TNFα secreted by HOK-16B cells, suggesting modulation of IL-8 through dentilisin-mediated degradation of TNFα. The addition of human serum to the culture potentiated the suppressive effect of T. denticola, resulting in substantial reductions of IL-8 and TNFα levels, even by K1. The serum-dependent effects of T. denticola were attributed to its ability to suppress the accumulation of intracellular reactive-oxygen species (ROS), a group of ubiquitous signaling molecules. Pretreatment with an antioxidant suppressed TNFα-induced IL-8 expression, confirming the role of ROS in TNFα signaling. Collectively, T. denticola targeted a key inflammatory cytokine and its signaling molecule to modulate the host innate immune response, which provides a new insight into modulation of host immunity by a periodontal pathogen.
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23
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The major outer sheath protein (Msp) of Treponema denticola has a bipartite domain architecture and exists as periplasmic and outer membrane-spanning conformers. J Bacteriol 2013; 195:2060-71. [PMID: 23457251 DOI: 10.1128/jb.00078-13] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The major outer sheath protein (Msp) is a primary virulence determinant in Treponema denticola, as well as the parental ortholog for the Treponema pallidum repeat (Tpr) family in the syphilis spirochete. The Conserved Domain Database (CDD) server revealed that Msp contains two conserved domains, major outer sheath protein(N) (MOSP(N)) and MOSP(C), spanning residues 77 to 286 and 332 to 543, respectively, within the N- and C-terminal regions of the protein. Circular dichroism (CD) spectroscopy, Triton X-114 (TX-114) phase partitioning, and liposome incorporation demonstrated that full-length, recombinant Msp (Msp(Fl)) and a recombinant protein containing MOSP(C), but not MOSP(N), form amphiphilic, β-sheet-rich structures with channel-forming activity. Immunofluorescence analysis of intact T. denticola revealed that only MOSP(C) contains surface-exposed epitopes. Data obtained using proteinase K accessibility, TX-114 phase partitioning, and cell fractionation revealed that Msp exists as distinct OM-integrated and periplasmic trimers. Msp(Fl) folded in Tris buffer contained slightly less β-sheet structure than detergent-folded Msp(Fl); both forms, however, partitioned into the TX-114 detergent-enriched phase. CDD analysis of the nine Tpr paralogs predicted to be outer membrane proteins (OMPs) revealed that seven have an Msp-like bipartite structure; phylogenetic analysis revealed that the MOSP(N) and MOSP(C) domains of Msp are most closely related to those of TprK. Based upon our collective results, we propose a model whereby a newly exported, partially folded intermediate can be either processed for OM insertion by the β-barrel assembly machinery (BAM) or remain periplasmic, ultimately forming a stable, water-soluble trimer. Extrapolated to T. pallidum, our model enables us to explain how individual Tprs can localize to either the periplasmic (e.g., TprK) or OM (e.g., TprC) compartments.
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24
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Goetting-Minesky MP, Godovikova V, Li JJ, Seshadrinathan S, Timm JC, Kamodia SS, Fenno JC. Conservation and revised annotation of the Treponema denticola prcB-prcA-prtP locus encoding the dentilisin (CTLP) protease complex. Mol Oral Microbiol 2012; 28:181-91. [PMID: 23253337 DOI: 10.1111/omi.12013] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/01/2012] [Indexed: 12/19/2022]
Abstract
Interstrain differences in antigenic surface proteins may reflect immunological pressure or differences in receptor specificity of the antigen. Treponema denticola exhibits considerable interstrain variability in its major surface protein (Msp), but no studies have addressed this issue in dentilisin (CTLP), a surface protease complex that has a significant role in T. denticola-host interactions in periodontal disease. Furthermore, the genome annotation of the prcB-prcA-prtP operon encoding dentilisin contains apparent errors and lacks a deduced PrtP amino acid sequence. To address these issues we analysed the protease operon from diverse T. denticola strains, as well as clones of the ATCC 35405 Type strain from which the genome sequence and original GenBank prtP sequence were derived. 6xHis-tagging of the PrtP C-terminus in ATCC 35405 demonstrated absence of the 'authentic frameshift' in PrtP reported in the genome databases. We propose that T. denticola genome annotations be updated to reflect this new information. PrcB and the PrtP N-terminal region that includes the catalytic domain were highly conserved in common laboratory strains and clinical isolates of T. denticola. Dentilisin proteolytic activity varied considerably between strains. Antibodies against PrcB, PrcA and PrtP from the type strain recognized these proteins in most T. denticola strains. PrtP varied up to 20% over the C-terminal 270 residues between strains. The PrtP C-terminal eight-residues (DWFYVEYP) was present in all strains, with two strains containing an additional Y-residue preceding the stop codon. Such conserved PrtP domains may be required for interactions with PrcA and PrcB, or for substrate interactions.
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Affiliation(s)
- M P Goetting-Minesky
- Department of Biologic and Materials Sciences, School of Dentistry, University of Michigan, Ann Arbor, MI 48109-1078, USA
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25
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Abstract
Oral Treponema species, most notably T. denticola, are implicated in the destructive effects of human periodontal disease. Progress in the molecular analysis of interactions between T. denticola and host proteins is reviewed here, with particular emphasis on the characterization of surface-expressed and secreted proteins of T. denticola involved in interactions with host cells, extracellular matrix components, and components of the innate immune system.
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Affiliation(s)
- J. Christopher Fenno
- Department of Biologic and Materials Sciences, School of Dentistry, University of Michigan, Ann Arbor, MI, USA
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26
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The antibacterial activity of LL-37 against Treponema denticola is dentilisin protease independent and facilitated by the major outer sheath protein virulence factor. Infect Immun 2011; 80:1107-14. [PMID: 22184422 DOI: 10.1128/iai.05903-11] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Host defense peptides are innate immune effectors that possess both bactericidal activities and immunomodulatory functions. Deficiency in the human host defense peptide LL-37 has previously been correlated with severe periodontal disease. Treponema denticola is an oral anaerobic spirochete closely associated with the pathogenesis of periodontal disease. The T. denticola major surface protein (MSP), involved in adhesion and cytotoxicity, and the dentilisin serine protease are key virulence factors of this organism. In this study, we examined the interactions between LL-37 and T. denticola. The three T. denticola strains tested were susceptible to LL-37. Dentilisin was found to inactivate LL-37 by cleaving it at the Lys, Phe, Gln, and Val residues. However, dentilisin deletion did not increase the susceptibility of T. denticola to LL-37. Furthermore, dentilisin activity was found to be inhibited by human saliva. In contrast, a deficiency of the T. denticola MSP increased resistance to LL-37. The MSP-deficient mutant bound less fluorescently labeled LL-37 than the wild-type strain. MSP demonstrated specific, dose-dependent LL-37 binding. In conclusion, though capable of LL-37 inactivation, dentilisin does not protect T. denticola from LL-37. Rather, the rapid, MSP-mediated binding of LL-37 to the treponemal outer sheath precedes cleavage by dentilisin. Moreover, in vivo, saliva inhibits dentilisin, thus preventing LL-37 restriction and ensuring its bactericidal and immunoregulatory activities.
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Composition and localization of Treponema denticola outer membrane complexes. Infect Immun 2011; 79:4868-75. [PMID: 21986628 DOI: 10.1128/iai.05701-11] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
The Treponema denticola outer membrane lipoprotein-protease complex (dentilisin) contributes to periodontal disease by degrading extracellular matrix components and disrupting intercellular host signaling pathways. We recently demonstrated that prcB, located upstream of and cotranscribed with prcA and prtP, encodes a 22-kDa lipoprotein that interacts with PrtP and is required for its activity. Here we further characterize products of the protease locus and their roles in expression, formation, and localization of outer membrane complexes. PrcB migrates in native gels as part of a >400-kDa complex that includes PrtP and PrcA, as well as the major outer sheath protein Msp. PrcB is detectable as a minor constituent of the purified active protease complex, which was previously reported to consist of only PrtP and auxiliary polypeptides PrcA1 and PrcA2. Though it lacks the canonical ribosome binding site present upstream of both prcA and prtP, PrcB is present at levels similar to those of PrtP in whole-cell extracts. Immunofluorescence microscopy demonstrated cell surface exposure of the mature forms of PrtP, PrcA1, PrcB, and Msp. The 16-kDa N-terminal acylated fragment of PrtP (predicted to be released during activation of PrtP) was present in cell extracts but was detected neither in the purified active protease complex nor on the cell surface. PrcA2, detectable on the surface of Msp-deficient cells but not that of wild-type cells, coimmunoprecipitated with Msp. Our results indicate that PrcB is a component of the outer membrane lipoprotein protease complex and that Msp and PrcA2 interaction may mediate formation of a very-high-molecular-weight outer membrane complex.
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Ishihara K, Wawrzonek K, Shaw LN, Inagaki S, Miyamoto M, Potempa J. Dentipain, a Streptococcus pyogenes IdeS protease homolog, is a novel virulence factor of Treponema denticola. Biol Chem 2011; 391:1047-55. [PMID: 20635859 DOI: 10.1515/bc.2010.113] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Treponema denticola is a major pathogen of chronic periodontitis. Analysis of the T. denticola genome revealed a gene orthologous with a cysteine protease-encoding gene from Streptococcus pyogenes (IdeS). IdeS interferes with IgG-dependent opsonophagocytosis by specific cleavage of IgG molecules. Analysis of this gene (termed ideT) revealed it to encode a two-domain protein whose N-terminus is composed of tandem immunoglobulin-like domains followed by a C-terminal IdeS-like protease domain. In this study we show that during secretion the IdeT protein is processed into an N-terminal fragment which remains associated with the cell, and a C-terminal part released into the medium. Although the secreted domain of IdeT, termed dentipain, shows only 25% identity to the IdeS protease, the putative catalytic cysteine and histidine residues are strongly conserved. Recombinant dentipain cleaves the insulin β-chain, an activity which is inhibited by E-64, a diagnostic inhibitor of cysteine proteases. Apart from insulin no cleavage of other protein substrates was detected, suggesting that dentipain has oligopeptidase activity. A mutant strain was constructed expressing a modified IdeT variant, the dentipain domain of which was deleted. This strain was found to be significantly reduced in its abscess-forming activity compared with the parental strain in a murine abscess model, suggesting that dentipain contributes to the virulence of T. denticola.
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Affiliation(s)
- Kazuyuki Ishihara
- Oral Health Science Center, Tokyo Dental College, Chiba 261-8502, Japan.
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McDowell JV, Frederick J, Miller DP, Goetting-Minesky MP, Goodman H, Fenno JC, Marconi RT. Identification of the primary mechanism of complement evasion by the periodontal pathogen, Treponema denticola. Mol Oral Microbiol 2010; 26:140-9. [PMID: 21375704 DOI: 10.1111/j.2041-1014.2010.00598.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Treponema denticola, a periodontal pathogen, binds the complement regulatory protein Factor H (FH). Factor H binding protein B (FhbB) is the sole FH binding protein produced by T. denticola. The interaction of FhbB with FH is unique in that FH is bound to the cell and then cleaved by the T. denticola protease, dentilisin. A ∼ 50-kDa product generated by dentilisin cleavage is retained at the cell surface. Until this study, a direct role for the FhbB-FH interaction in complement evasion and serum sensitivity had not been demonstrated. Here we assess the serum resistance of T. denticola strain 35405 (Td35405wt) and isogenic mutants deficient in dentilisin (Td35405-CCE) and FhbB production (Td35405ΔfhbB), respectively. Both dentilisin and FhbB have been postulated to be key virulence factors that mediate complement evasion. Consistent with conditions in the subgingival crevice, an environment with a significant concentration of complement, Td35405wt was resistant to serum concentrations as high as 25%. Deletion of fhbB (Td35405ΔfhbB), which resulted in the complete loss of FH binding ability, but not inactivation of dentilisin activity (Td35405-CCE), rendered T. denticola highly sensitive to 25% human serum with 80% of the cells being disrupted after 4 h of incubation. Heat treatment of the serum to inactivate complement confirmed that killing was mediated by complement. These results indicate that the FH-FhbB interaction is required for serum resistance whereas dentilisin is not. This report provides new insight into the novel complement evasion mechanisms of T. denticola.
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Affiliation(s)
- J V McDowell
- Department of Microbiology and Immunology, Medical College of Virginia, Virginia Commonwealth University, Richmond, VA, USA
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Ito R, Ishihara K, Shoji M, Nakayama K, Okuda K. Hemagglutinin/Adhesin domains ofPorphyromonas gingivalisplay key roles in coaggregation withTreponema denticola. ACTA ACUST UNITED AC 2010; 60:251-60. [DOI: 10.1111/j.1574-695x.2010.00737.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Dashper SG, Seers CA, Tan KH, Reynolds EC. Virulence factors of the oral spirochete Treponema denticola. J Dent Res 2010; 90:691-703. [PMID: 20940357 DOI: 10.1177/0022034510385242] [Citation(s) in RCA: 121] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
There is compelling evidence that treponemes are involved in the etiology of several chronic diseases, including chronic periodontitis as well as other forms of periodontal disease. There are interesting parallels with other chronic diseases caused by treponemes that may indicate similar virulence characteristics. Chronic periodontitis is a polymicrobial disease, and recent animal studies indicate that co-infection of Treponema denticola with other periodontal pathogens can enhance alveolar bone resorption. The bacterium has a suite of molecular determinants that could enable it to cause tissue damage and subvert the host immune response. In addition to this, it has several non-classic virulence determinants that enable it to interact with other pathogenic bacteria and the host in ways that are likely to promote disease progression. Recent advances, especially in molecular-based methodologies, have greatly improved our knowledge of this bacterium and its role in disease.
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Affiliation(s)
- S G Dashper
- Cooperative Research Centre for Oral Health, Melbourne Dental School and Bio21 Institute, The University of Melbourne, 720 Swanston Street, Victoria 3010, Australia
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Comparative genomic analyses of attenuated strains of Mycoplasma gallisepticum. Infect Immun 2010; 78:1760-71. [PMID: 20123709 DOI: 10.1128/iai.01172-09] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Mycoplasma gallisepticum is a significant respiratory and reproductive pathogen of domestic poultry. While the complete genomic sequence of the virulent, low-passage M. gallisepticum strain R (R(low)) has been reported, genomic determinants responsible for differences in virulence and host range remain to be completely identified. Here, we utilize genome sequencing and microarray-based comparative genomic data to identify these genomic determinants of virulence and to elucidate genomic variability among strains of M. gallisepticum. Analysis of the high-passage, attenuated derivative of R(low), R(high), indicated that relatively few total genomic changes (64 loci) occurred, yet they are potentially responsible for the observed attenuation of this strain. In addition to previously characterized mutations in cytadherence-related proteins, changes included those in coding sequences of genes involved in sugar metabolism. Analyses of the genome of the M. gallisepticum vaccine strain F revealed numerous differences relative to strain R, including a highly divergent complement of vlhA surface lipoprotein genes, and at least 16 genes absent or significantly fragmented relative to strain R. Notably, an R(low) isogenic mutant in one of these genes (MGA_1107) caused significantly fewer severe tracheal lesions in the natural host compared to virulent M. gallisepticum R(low). Comparative genomic hybridizations indicated few genetic loci commonly affected in F and vaccine strains ts-11 and 6/85, which would correlate with proteins affecting strain R virulence. Together, these data provide novel insights into inter- and intrastrain M. gallisepticum genomic variability and the genetic basis of M. gallisepticum virulence.
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Brissette CA, Pham TTT, Coats SR, Darveau RP, Lukehart SA. Treponema denticola does not induce production of common innate immune mediators from primary gingival epithelial cells. ACTA ACUST UNITED AC 2009; 23:474-81. [PMID: 18954353 DOI: 10.1111/j.1399-302x.2008.00452.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
It has been hypothesized that the neutrophil chemoattractant interleukin-8 (IL-8) forms a gradient in the oral cavity, with the highest concentration of IL-8 produced closest to the bacterial biofilm. In periodontitis, this gradient is disrupted, impairing neutrophil chemotaxis to diseased sites. Treponema denticola is prominently associated with periodontal disease, yet little is known about its ability to modulate the production of inflammatory mediators by epithelial cells. Others have shown that dentilisin, the major outer membrane protease of T. denticola, degrades IL-8 in vitro. We now provide evidence that T. denticola also fails to induce IL-8 production from primary gingival epithelial cells (PGEC). The lack of IL-8 production is not explained by IL-8 degradation, because a protease mutant that does not degrade IL-8 does not induce IL-8 production with these stimuli either. The lack of innate immune mediator production may be a more global phenomenon because T. denticola fails to induce IL-6 or intercellular adhesion molecule 1 production from PGEC. T. denticola also fails to induce transcription of IL-8 and human beta-defensin-2 messenger RNA. The lack of immune mediator production is not explained by the failure of T. denticola to interact with Toll-like receptor 2 (TLR-2), as T. denticola stimulates nuclear factor-kappaB nuclear translocation in TLR-2-transfected HEK293 cells. Not only can T. denticola degrade the IL-8 present in the periodontal lesion, but this organism also fails to induce IL-8 production by PGEC. The lack of an epithelial cell response to T. denticola may contribute to the pathogenesis of periodontitis by failing to trigger chemotaxis of neutrophils into the periodontal pocket.
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Affiliation(s)
- C A Brissette
- Department of Pathobiology, University of Washington, Seattle, WA, USA
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Rosen G, Genzler T, Sela MN. Coaggregation of Treponema denticola with Porphyromonas gingivalis and Fusobacterium nucleatum is mediated by the major outer sheath protein of Treponema denticola. FEMS Microbiol Lett 2009; 289:59-66. [PMID: 19054094 DOI: 10.1111/j.1574-6968.2008.01373.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Coagreggation of Treponema denticola with either Porphyromonas gingivalis or Fusobacterium nucleatum was characterized and the role of the major outer sheath protein (MSP) in the coaggregation process of these bacteria was evaluated. The MSP of T. denticola was found to be able to bind to P. gingivalis and F. nucleatum cells and this binding could be inhibited by MSP in a concentration-dependent manner. While sodium dodecyl sulfate polyacrylamide gel electrophoresis and Periodic acid-Schiff (PAS) staining of MSP revealed that it is a glycoprotein, monosaccharide analysis showed that MSP contains: Glc (44.4), Gal (20.4%) GlcN (1.3%), GalN (31.6%) and Fuc (9.2%). Peptide N-glycosidase F deglycosylation of MSP was found to inhibit its binding to F. nucleatum but not to P. gingivalis cells. Sugar-binding studies showed that the requirements for the binding of both T. denticola and MSP to F. nucleatum cells are similar to those of the F. nucleatum galactose-binding lectin. These data suggest that MSP acts as an adhesin during the coaggregation process of T. denticola with P. gingivalis and F. nucleatum through its protein and carbohydrate moieties, respectively.
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Affiliation(s)
- Graciela Rosen
- Laboratory of Oral Microbiology and Ecology, Faculty of Dental Medicine, The Hebrew University-Hadassah, Jerusalem, Israel.
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Immune response and alveolar bone resorption in a mouse model of Treponema denticola infection. Infect Immun 2008; 77:694-8. [PMID: 19015247 DOI: 10.1128/iai.01004-08] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Treponema denticola is considered to be an agent strongly associated with periodontal disease. The lack of an animal infection model has hampered the understanding of T. denticola pathogenesis and the host's immune response to infection. In this study, we have established an oral infection model in mice, demonstrating that infection by oral inoculation is feasible. The presence of T. denticola in the oral cavities of the animals was confirmed by PCR. Mice given T. denticola developed a specific immune response to the bacterium. The antibodies generated from the infection were mainly of the immunoglobulin G1 subclass, indicating a Th2-tilted response. The antibodies recognized 11 T. denticola proteins, of which a 62-kDa and a 53-kDa protein were deemed immunodominant. The two proteins were identified, respectively, as dentilisin and the major outer sheath protein by mass spectrometry. Splenocytes cultured from the infected mice no longer produced interleukin-10 and produced markedly reduced levels of gamma interferon relative to those produced by naïve splenocytes upon stimulation with T. denticola. Mandibles of infected mice showed significantly greater bone resorption (P < 0.01) than those of mock-infected controls.
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Kuramitsu HK, Chi B, Ikegami A. Genetic manipulation of Treponema denticola. CURRENT PROTOCOLS IN MICROBIOLOGY 2008; Chapter 12:Unit 12B.2. [PMID: 18770552 DOI: 10.1002/9780471729259.mc12b02s00] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The oral anaerobic spirochete, Treponema denticola, has been implicated in the etiology of human periodontal diseases; however, the molecular basis for the virulence of these organisms is still unclear. Potential pathogenic factors expressed by T. denticola have recently begun to be identified through the development of gene transfer approaches in this organism following electroporetic transformation. Several antibiotic resistance markers have been developed for use in the construction of monospecific mutants in these organisms. In addition, these antibiotic resistance cassettes have been more recently utilized to construct shuttle plasmids for complementation analysis of the mutants. These plasmids were also used to express heterologous spirochete genes in T. denticola. The transformation of other spirochetes such as T. phagedenis with these plasmids further suggests that it should be possible to develop similar gene transfer systems in other cultivable treponemes.
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Capone R, Wang HT, Ning Y, Sweier DG, Lopatin DE, Fenno JC. Human serum antibodies recognize Treponema denticola Msp and PrtP protease complex proteins. ACTA ACUST UNITED AC 2008; 23:165-9. [PMID: 18279185 DOI: 10.1111/j.1399-302x.2007.00404.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND/AIMS Treponema denticola outer membrane proteins are postulated to have key roles in microbe-host interactions in periodontitis. Because there are no reports of in vivo expression of these putative virulence factors, we examined several T. denticola strains to determine whether sera from human subjects recognized specific T. denticola outer membrane proteins. METHODS Soluble extracts were prepared from exponential phase cultures of T. denticola strains representing three serotypes, from defined T. denticola mutants defective in Msp (major surface protein) or PrtP lipoprotein protease complex (CTLP; dentilisin), and Escherichia coli strains expressing distinctly different T. denticola Msp. Extracts were subjected to Western immunoassays using archived human serum samples. RESULTS Human serum antibodies (immunoglobulin G class) recognized multiple protein bands in T. denticola strains. In the parent strain ATCC 35405, these included bands at 72-, 53-, 40-, and 30-kDa. Bands corresponding to Msp and the PrtP protease complex proteins were absent in isogenic msp and protease complex mutants, respectively. Individual human sera showed specificity for one or more Msp types. CONCLUSIONS This is the first definitive report of human serum antibody responses to specific T. denticola antigens. T. denticola Msp and the proteins comprising the PrtP lipoprotein protease complex are expressed in vivo and are immunogenic in humans. Human antibody recognition of Msp exhibits strain specificity and is consistent with strain serotyping. These results demonstrate the utility of T. denticola isogenic mutants in characterizing host immune responses to periodontal pathogens.
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Affiliation(s)
- R Capone
- Department of Biologic and Materials Sciences, University of Michigan, Ann Arbor, MI, USA
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Brissette CA, Lukehart SA. Mechanisms of decreased susceptibility to beta-defensins by Treponema denticola. Infect Immun 2007; 75:2307-15. [PMID: 17325047 PMCID: PMC1865744 DOI: 10.1128/iai.01718-06] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Treponema denticola, a periodontal pathogen, is relatively resistant to human beta-defensins, which are small cationic antimicrobial peptides produced by a number of cells, including the gingival epithelium. Using two independent methods, we previously demonstrated that T. denticola proteases are not responsible for decreased vulnerability to defensins. In this study, we confirmed that the major outer membrane protease, dentilisin, is not responsible for T. denticola insensitivity to defensins and examined several other possible mechanisms, including reduced binding to the bacterial surface and efflux pump activity. It has been suggested that some bacteria mask their surfaces with serum proteins. T. denticola grown in a serum-free medium did not exhibit increased susceptibility to human beta-defensin 2 and 3 (hbetaD-2 and hbetaD-3, respectively), suggesting that cloaking of the outer surface with host proteins is not involved in defensin resistance. Nonetheless, we demonstrated that T. denticola binds significantly less hbetaD-2 and -3 than susceptible organisms bind, suggesting that the unusual outer membrane composition of T. denticola may discourage cationic peptide binding. Efflux pumps have been shown to mediate resistance to antibiotics and cationic peptides in other bacteria, and their role in T. denticola's relative resistance to beta-defensins was investigated. Three inhibitors of bacterial ATP-binding cassette (ABC) efflux pumps had no effect on T. denticola's susceptibility to hbetaD-2 or -3. In contrast, a proton motive force inhibitor, carbonyl cyanide 3-chlorophenylhydrazone, increased the susceptibility of T. denticola to killing by hbetaD-3, demonstrating a potential role for efflux pumps (other than ABC pumps) in resistance to this peptide. Our data suggest that the combination of decreased defensin binding and efflux of any peptide which enters the cytoplasm may explain T. denticola's relative resistance to human beta-defensins.
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Affiliation(s)
- Catherine A Brissette
- Department of Pathobiology, University of Washington, Seattle, Washington 98195, USA
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Miyamoto M, Ishihara K, Okuda K. The Treponema denticola surface protease dentilisin degrades interleukin-1 beta (IL-1 beta), IL-6, and tumor necrosis factor alpha. Infect Immun 2006; 74:2462-7. [PMID: 16552080 PMCID: PMC1418930 DOI: 10.1128/iai.74.4.2462-2467.2006] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Dentilisin is a major surface protease and virulence factor of the bacterium Treponema denticola. In this study, we found that T. denticola reduced inflammatory cytokines, including interleukin-1beta (IL-1beta), IL-6, and tumor necrosis factor alpha, in peripheral blood mononuclear cells through degradation by dentilisin.
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Affiliation(s)
- Meguru Miyamoto
- Department of Microbiology, Tokyo Dental College, 1-2-2 Masago, Mihama-ku, Chiba 261-8502, Japan.
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41
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Yamazaki T, Miyamoto M, Yamada S, Okuda K, Ishihara K. Surface protease of Treponema denticola hydrolyzes C3 and influences function of polymorphonuclear leukocytes. Microbes Infect 2006; 8:1758-63. [PMID: 16815066 DOI: 10.1016/j.micinf.2006.02.013] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2005] [Revised: 02/02/2006] [Accepted: 02/08/2006] [Indexed: 10/24/2022]
Abstract
Treponema denticola is a dominant microorganism in human periodontal lesions. One of the major virulence factors of this microorganism is its chymotrypsin-like surface protease, dentilisin. The purpose of this study was to evaluate the effect of dentilisin on human polymorphonuclear leukocytes (PMNs). We used chemiluminescence to assess production of O(-)(2) by PMNs against T. denticola ATCC 35405 and dentilisin-deficient mutant K1. T. denticola ATCC 35405 induced production of O(-)(2), whereas dentilisin-deficient K1 did not. We found that chymostatin, a protease inhibitor, strongly reduced the ability of T. denticola ATCC 35405 to induce production of, O(-)(2), whereas K1 was relatively unaffected. We also used Immunoblot and ELISA to evaluate the activation of complement by this microorganism in relation to PMNs. T. denticola ATCC 35405 hydrolyzed the alpha-chain of C3, producing iC3b. Furthermore, strain ATCC 35405 induced a larger release of MMP-9 from PMNs than strain K1. Dentilisin activated PMNs via complement pathways and may play a role in establishing periodontal lesions.
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Affiliation(s)
- Tomoko Yamazaki
- Department of Periodontics, Tokyo Dental College, 1-2-2 Masago, Chiba, Japan
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Yamada M, Ikegami A, Kuramitsu HK. Synergistic biofilm formation byTreponema denticolaandPorphyromonas gingivalis. FEMS Microbiol Lett 2005; 250:271-7. [PMID: 16085371 DOI: 10.1016/j.femsle.2005.07.019] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2005] [Revised: 07/13/2005] [Accepted: 07/14/2005] [Indexed: 11/29/2022] Open
Abstract
Biofilm formation is an important step in the etiology of periodontal diseases. In this study, in vitro biofilm formation by Treponema denticola and Porphyromonas gingivalis 381 displayed synergistic effects. Confocal microscopy demonstrated that P. gingivalis attaches to the substratum first as a primary colonizer followed by coaggregation with T. denticola to form a mixed biofilm. The T. denticola flagella mutant as well as the cytoplasmic filament mutant were shown to be essential for biofilm formation as well as coaggregation with P. gingivalis. The major fimbriae and Arg-gingipain B of P. gingivalis also play important roles in biofilm formation with T. denticola.
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Affiliation(s)
- Mitsunori Yamada
- Department of Oral Biology, State University of New York, Buffalo, NY 14214, USA
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43
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Holt SC, Ebersole JL. Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia: the "red complex", a prototype polybacterial pathogenic consortium in periodontitis. Periodontol 2000 2005; 38:72-122. [PMID: 15853938 DOI: 10.1111/j.1600-0757.2005.00113.x] [Citation(s) in RCA: 629] [Impact Index Per Article: 33.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Stanley C Holt
- Department of Periodontology, The Forsyth Institute, Boston, MA, USA
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Affiliation(s)
- Richard P Ellen
- Faculty of Dentistry, University of Toronto, Toronto, Ontario, Canada
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45
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Edwards AM, Jenkinson HF, Woodward MJ, Dymock D. Binding properties and adhesion-mediating regions of the major sheath protein of Treponema denticola ATCC 35405. Infect Immun 2005; 73:2891-8. [PMID: 15845495 PMCID: PMC1087326 DOI: 10.1128/iai.73.5.2891-2898.2005] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
There is growing evidence that a number of oral Treponema species, in particular Treponema denticola, are associated with the progression of human periodontal disease. The major sheath (or surface) protein (Msp) of T. denticola is implicated in adhesion of bacteria to host cells and tissue proteins and is likely to be an important virulence factor. However, the binding regions of the Msp are not known. We have purified from Escherichia coli recombinant Msp (rMsp) polypeptides corresponding to the following: full-length Msp (rMsp) minus 13 N-terminal amino acid (aa) residues, an amino-terminal fragment (rN-Msp, 189 aa residues), a 57-aa residue segment from the central region (rV-Msp), and a C-terminal fragment (rC-Msp, 272 aa residues). rMsp (530 aa residues) bound to immobilized fibronectin, keratin, laminin, collagen type I, fibrinogen, hyaluronic acid, and heparin. The N- and V-region polypeptides, but not rC-Msp, also bound to these substrates. Binding of rMsp to fibronectin was targeted to the N-terminal heparin I/fibrin I domain. Antibodies to the N-region or V-region polypeptides, but not antibodies to the rC-Msp fragment, blocked adhesion of T. denticola ATCC 35405 cells to a range of host protein molecules. These results suggest that the N-terminal half of Msp carries epitopes that are surface exposed and that are involved in mediating adhesion. Binding of rMsp onto the cell surface of low-level fibronectin-binding Treponema isolates conferred a 10-fold increase in fibronectin binding. This confirms that Msp functions autonomously as an adhesin and raises the possibility that phenotypic complementation of virulence functions might occur within mixed populations of Treponema species.
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Affiliation(s)
- Andrew M Edwards
- Oral Microbiology Unit, Department of Oral and Dental Science, University of Bristol, Lower Maudlin Street, Bristol BS1 2LY, United Kingdom.
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Miura T, Ishihara K, Kato T, Kimizuka R, Miyabe H, Ando T, Uchiyama T, Okuda K. Detection of heat shock proteins but not superantigen by isolated oral bacteria from patients with Behcet's disease. ACTA ACUST UNITED AC 2005; 20:167-71. [PMID: 15836518 DOI: 10.1111/j.1399-302x.2005.00207.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
We isolated bacteria from periodontal sites and mixed saliva in eight patients with Behcet's disease and surveyed them to determine whether they produced heat shock proteins (HSPs) and superantigen. Cultivable bacterial compositions from periodontal sites and saliva were examined by anaerobic culture using blood agar plates. Gram-negative anaerobic rods such as Prevotella intermedia, Fusobacterium nucleatum, and Capnocytophaga species were predominant in the isolates from the subgingival plaque samples. The Streptococcus mitis group was the most common type isolated from the saliva samples. To detect the production of HSPs, Western blot analyses were performed using a polyclonal rabbit antibody to Escherichia coli DnaK and a monoclonal antibody to Helicobacter pylori Gro-EL. Sonic extracts of 27 of the strains (79.4%) reacted with the antibody against E. coli DnaK. Nine of these 34 strains (26.5%) were found to produce HSPs that reacted with antibody to H. pylori Gro-EL. A total of 54 isolates were examined for superantigen activity against human peripheral leukocytes. Twenty-five gram-negative clinical strains isolated from chronic periodontitis lesions and 20 ATCC strains of microorganisms were also examined. We could not detect any superantigen activity in 500x diluted supernatant of the strains isolated from the eight patients with Behcet's disease. The present study indicates that the anaerobic strains isolated from the oral cavity of these patients produce HSPs, the production being related to Bechet's disease.
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Affiliation(s)
- T Miura
- Department of Microbiology, Tokyo Dental College, Chiba, Japan
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Abstract
Pathogenic spirochetes are the causative agents of several important diseases including syphilis, Lyme disease, leptospirosis, swine dysentery, periodontal disease and some forms of relapsing fever. Spirochetal bacteria possess two membranes and the proteins present in the outer membrane are at the site of interaction with host tissue and the immune system. This review describes the current knowledge in the field of spirochetal outer membrane protein (OMP) biology. What is known concerning biogenesis and structure of OMPs, with particular regard to the atypical signal peptide cleavage sites observed amongst the spirochetes, is discussed. We examine the functions that have been determined for several spirochetal OMPs including those that have been demonstrated to function as adhesins, porins or to have roles in complement resistance. A detailed description of the role of spirochetal OMPs in immunity, including those that stimulate protective immunity or that are involved in antigenic variation, is given. A final section is included which covers experimental considerations in spirochetal outer membrane biology. This section covers contentious issues concerning cellular localization of putative OMPs, including determination of surface exposure. A more detailed knowledge of spirochetal OMP biology will hopefully lead to the design of new vaccines and a better understanding of spirochetal pathogenesis.
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Affiliation(s)
- Paul A. Cullen
- Australian Bacterial Pathogenesis Program, Department of Microbiology, Monash University, Melbourne, Vic. 3800, Australia
- Victorian Bioinformatics Consortium, Monash University, Vic. 3800, Australia
| | - David A. Haake
- School of Medicine, University of California at Los Angeles, Los Angeles, CA 90095, USA
- Division of Infectious Diseases, Veteran Affairs Greater Los Angeles Healthcare System, Los Angeles, CA 90073, USA
| | - Ben Adler
- Australian Bacterial Pathogenesis Program, Department of Microbiology, Monash University, Melbourne, Vic. 3800, Australia
- Victorian Bioinformatics Consortium, Monash University, Vic. 3800, Australia
- Corresponding author. Tel.: +61-3-9905-4815; fax: +61-3-9905-4811. E-mail address: (B. Adler)
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Vesey PM, Kuramitsu HK. Genetic analysis of Treponema denticola ATCC 35405 biofilm formation. Microbiology (Reading) 2004; 150:2401-2407. [PMID: 15256581 DOI: 10.1099/mic.0.26816-0] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Treponema denticola is a major aetiological organism implicated in periodontal disease. The interaction of T. denticola with other oral bacteria, in particular Porphyromonas gingivalis, in biofilm formation is thought to be an important step in the onset of periodontal disease. The interaction between T. denticola and P. gingivalis has been examined using a panel of T. denticola mutants and their effects on mixed biofilm formation tested in a static biofilm model. T. denticola ATCC 35405 did not form detectable biofilms on various inert surfaces. However, the spirochaete was demonstrated to form a biofilm with preattached P. gingivalis 381. T. denticola cfpA, which lacks the cytoplasmic filament, was unable to produce a mixed biofilm with P. gingivalis. A T. denticola flgE mutant which lacks the flagella hook protein and is therefore non-motile displayed a reduced, but readily detectable, ability to form a mixed biofilm as did the T. denticola mutant which does not possess the major outer sheath protein (Msp). The T. denticola lrrA mutant was only moderately defective in forming mixed biofilms with P. gingivalis. However, the T. denticola methyl-accepting chemotaxis protein (DmcA) did not appear to play a major role in mixed biofilm formation. In contrast, T. denticola lacking the PrtP protein for prolyl-phenylalanine-specific protease, showed an increased ability to form mixed biofilms and a prolonged viability in the biofilm.
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Affiliation(s)
- Peter M Vesey
- Department of Oral Biology, State University of New York at Buffalo, 3435 Main Street, Buffalo, NY 14214-3092, USA
| | - Howard K Kuramitsu
- Department of Oral Biology, State University of New York at Buffalo, 3435 Main Street, Buffalo, NY 14214-3092, USA
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O'Brien-Simpson NM, Veith PD, Dashper SG, Reynolds EC. Antigens of bacteria associated with periodontitis. Periodontol 2000 2004; 35:101-34. [PMID: 15107060 DOI: 10.1111/j.0906-6713.2004.003559.x] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Neil M O'Brien-Simpson
- Centre for Oral Health Science, School of Dental Science, The University of Melbourne, Victoria, Australia
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Batista da Silva AP, Lee W, Bajenova E, McCulloch CAG, Ellen RP. The major outer sheath protein of Treponema denticola inhibits the binding step of collagen phagocytosis in fibroblasts. Cell Microbiol 2004; 6:485-98. [PMID: 15056218 DOI: 10.1111/j.1462-5822.2004.00377.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Bacterial infections contribfute to the chronicity of connective tissue lesions in part by perturbing extracellular matrix remodelling processes. We examined a novel mechanism by which the major outer sheath protein (Msp) of the spirochaete Treponema denticola disrupts matrix remodelling mediated by intracellular digestion of collagen. The initial collagen-binding step of phagocytosis was examined in human gingival fibroblasts and Rat-2 fibroblasts. Cells were pretreated with Msp or vehicle, and binding of collagen-coated beads was measured by flow cytometry. Exposure to Msp induced a dose- and time-dependent decrease in cells that bound collagen beads; the inhibition of binding was reversed by absorption with anti-Msp antibodies. Msp-treated fibroblasts remained viable but underwent actin reorganization, including the assembly of a dense meshwork of subcortical actin filaments. Shear force assays showed that Msp abrogated collagen-binding interactions in the minimal affinity range required for stable adhesion. Fluorescence microscopy and immunoblotting showed equivalent amounts of beta1 integrin associated with collagen beads bound to Msp- and vehicle-treated cells. Photobleaching experiments found a similar percentage mobile fraction of beta1 integrins recovered in bleached areas of the plasma membrane. In contrast, Msp-induced inhibition of collagen binding was reversed by beta1 integrin affinity-activating antibodies and by latrunculin B, which prevented subcortical actin assembly. We conclude that native Msp of T. denticola inhibits the binding step of collagen phagocytosis in fibroblasts by inducing subcortical actin filament assembly and restricting affinity modulation of beta1 integrins. We suggest that, like Msp, bacterial toxins that target the cytoskeleton may also perturb the signalling networks required for cellular engagement of matrix ligands.
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Affiliation(s)
- Andre Paes Batista da Silva
- CIHR Group in Matrix Dynamics, University of Toronto, 124 Edward Street, Room 450, Toronto, Ontario, Canada M5G 1G6
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