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Mann AE, Aumend C, Crull S, O'Connell LM, Osagie E, Akhigbe P, Obuekwe O, Omoigberale A, Rowe M, Blouin T, Soule A, Kelly C, Burne RA, Coker MO, Richards VP. HIV Infection and Exposure Increases Cariogenic Taxa, Reduces Taxonomic Turnover, and Homogenizes Spatial Differentiation for the Supragingival Microbiome. RESEARCH SQUARE 2024:rs.3.rs-4720457. [PMID: 39149457 PMCID: PMC11326420 DOI: 10.21203/rs.3.rs-4720457/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/17/2024]
Abstract
Background The oral microbiome comprises distinct microbial communities that colonize diverse ecological niches across the oral cavity, the composition of which are influenced by nutrient and substrate availability, host genetics, diet, behavior, age, and other diverse host and environmental factors. Unlike other densely populated human-associated microbial ecosystems (e.g., gut, urogenital), the oral microbiome is regularly and directly exposed to the external environment and is therefore likely less stable over time. Cross sectional studies of the oral microbiome capture a glimpse of this temporal dynamism, yet a full appreciation of the relative stability, robusticity, and spatial structure of the oral environment is necessary to understand the role of microbial communities in promoting health or disease. Results Here we investigate the spatial and temporal stability of the oral microbiome over three sampling time points in the context of HIV infection and exposure. Individual teeth were sampled from a cohort of 565 Nigerian children with varying levels of tooth decay severity (i.e., caries disease). We collected 1,960 supragingival plaque samples and characterized the oral microbiome using a metataxonomic approach targeting an approximately 478 bp region of the bacterial rpo C gene. We found that both infection and exposure to HIV have significant effects on the stability of the supragingival plaque microbiome at both the spatial and temporal scale. Specifically, we detect (1) significantly lower taxonomic turnover of the oral community among exposed and infected children compared to unexposed children, (2) we find that HIV infection homogenizes the oral community across the anterior and posterior dentition, and (3) that impaired immunity (i.e., low CD4 count) and low taxonomic turnover over time in children living with HIV is associated with higher frequency of cariogenic taxa including Streptococcus mutans . Conclusions Our results document substantial community fluctuations over time in children unexposed to HIV independent of oral health status. This suggests that the oral community, under typical conditions, rapidly adapts to environmental perturbations to maintain homeostasis and that long-term taxonomic rigidity is a signal of community dysfunction, potentially leading to a higher incidence of oral disease including caries.
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Regueira-Iglesias A, Vázquez-González L, Balsa-Castro C, Vila-Blanco N, Blanco-Pintos T, Tamames J, Carreira MJ, Tomás I. In silico evaluation and selection of the best 16S rRNA gene primers for use in next-generation sequencing to detect oral bacteria and archaea. MICROBIOME 2023; 11:58. [PMID: 36949474 PMCID: PMC10035280 DOI: 10.1186/s40168-023-01481-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Accepted: 01/30/2023] [Indexed: 06/18/2023]
Abstract
BACKGROUND Sequencing has been widely used to study the composition of the oral microbiome present in various health conditions. The extent of the coverage of the 16S rRNA gene primers employed for this purpose has not, however, been evaluated in silico using oral-specific databases. This paper analyses these primers using two databases containing 16S rRNA sequences from bacteria and archaea found in the human mouth and describes some of the best primers for each domain. RESULTS A total of 369 distinct individual primers were identified from sequencing studies of the oral microbiome and other ecosystems. These were evaluated against a database reported in the literature of 16S rRNA sequences obtained from oral bacteria, which was modified by our group, and a self-created oral archaea database. Both databases contained the genomic variants detected for each included species. Primers were evaluated at the variant and species levels, and those with a species coverage (SC) ≥75.00% were selected for the pair analyses. All possible combinations of the forward and reverse primers were identified, with the resulting 4638 primer pairs also evaluated using the two databases. The best bacteria-specific pairs targeted the 3-4, 4-7, and 3-7 16S rRNA gene regions, with SC levels of 98.83-97.14%; meanwhile, the optimum archaea-specific primer pairs amplified regions 5-6, 3-6, and 3-6, with SC estimates of 95.88%. Finally, the best pairs for detecting both domains targeted regions 4-5, 3-5, and 5-9, and produced SC values of 95.71-94.54% and 99.48-96.91% for bacteria and archaea, respectively. CONCLUSIONS Given the three amplicon length categories (100-300, 301-600, and >600 base pairs), the primer pairs with the best coverage values for detecting oral bacteria were as follows: KP_F048-OP_R043 (region 3-4; primer pair position for Escherichia coli J01859.1: 342-529), KP_F051-OP_R030 (4-7; 514-1079), and KP_F048-OP_R030 (3-7; 342-1079). For detecting oral archaea, these were as follows: OP_F066-KP_R013 (5-6; 784-undefined), KP_F020-KP_R013 (3-6; 518-undefined), and OP_F114-KP_R013 (3-6; 340-undefined). Lastly, for detecting both domains jointly they were KP_F020-KP_R032 (4-5; 518-801), OP_F114-KP_R031 (3-5; 340-801), and OP_F066-OP_R121 (5-9; 784-1405). The primer pairs with the best coverage identified herein are not among those described most widely in the oral microbiome literature. Video Abstract.
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Affiliation(s)
- Alba Regueira-Iglesias
- Oral Sciences Research Group, Department of Surgery and Medical-Surgical Specialties, School of Medicine and Dentistry, Universidade de Santiago de Compostela, Health Research Institute Foundation of Santiago (FIDIS), C/ Entrerrios s/n, 15872 Santiago de Compostela, Spain
| | - Lara Vázquez-González
- Centro Singular de Investigación en Tecnoloxías Intelixentes and Departamento de Electrónica e Computación, Universidade de Santiago de Compostela, Health Research Institute Foundation of Santiago (FIDIS), Rúa de Jenaro de la Fuente, s/n, 15705 Santiago de Compostela, Spain
| | - Carlos Balsa-Castro
- Oral Sciences Research Group, Department of Surgery and Medical-Surgical Specialties, School of Medicine and Dentistry, Universidade de Santiago de Compostela, Health Research Institute Foundation of Santiago (FIDIS), C/ Entrerrios s/n, 15872 Santiago de Compostela, Spain
| | - Nicolás Vila-Blanco
- Centro Singular de Investigación en Tecnoloxías Intelixentes and Departamento de Electrónica e Computación, Universidade de Santiago de Compostela, Health Research Institute Foundation of Santiago (FIDIS), Rúa de Jenaro de la Fuente, s/n, 15705 Santiago de Compostela, Spain
| | - Triana Blanco-Pintos
- Oral Sciences Research Group, Department of Surgery and Medical-Surgical Specialties, School of Medicine and Dentistry, Universidade de Santiago de Compostela, Health Research Institute Foundation of Santiago (FIDIS), C/ Entrerrios s/n, 15872 Santiago de Compostela, Spain
| | - Javier Tamames
- Microbiome Analysis Laboratory, Systems Biology Department, Centro Nacional de Biotecnología (CNB)-CSIC, Madrid, Spain
| | - Maria José Carreira
- Centro Singular de Investigación en Tecnoloxías Intelixentes and Departamento de Electrónica e Computación, Universidade de Santiago de Compostela, Health Research Institute Foundation of Santiago (FIDIS), Rúa de Jenaro de la Fuente, s/n, 15705 Santiago de Compostela, Spain
| | - Inmaculada Tomás
- Oral Sciences Research Group, Department of Surgery and Medical-Surgical Specialties, School of Medicine and Dentistry, Universidade de Santiago de Compostela, Health Research Institute Foundation of Santiago (FIDIS), C/ Entrerrios s/n, 15872 Santiago de Compostela, Spain
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Belkhou C, Tadeo RT, Bacigalupe R, Valles-Colomer M, Chaffron S, Joossens M, Obregon A, Marín Reyes L, Trujillo O, Huys GRB, Raes J. Treponema peruense sp. nov., a commensal spirochaete isolated from human faeces. Int J Syst Evol Microbiol 2021; 71. [PMID: 34672919 PMCID: PMC8604162 DOI: 10.1099/ijsem.0.005050] [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] [Indexed: 01/11/2023] Open
Abstract
A Gram-stain-negative, obligatory anaerobic spirochaete (RCC2812T) was isolated from a faecal sample obtained from an individual residing in a remote Amazonian community in Peru. The bacterium showed highest 16S rRNA gene sequence similarity to the pig intestinal spirochete Treponema succinifaciens (89.48 %). Average nucleotide identity values between strain RCC2812T and all available Treponema genomes from validated type strains were all <73 %, thus clearly lower than the species delineation threshold. The DNA G+C content of RCC2812T was 41.24 mol%. Phenotypic characterization using the API-ZYM and API 20A systems confirmed the divergent position of this bacterium within the genus Treponema. Strain RCC2812T could be differentiated from the phylogenetically most closely related T. succinifaciens by the presence of alkaline phosphatase and α -glucosidase activities. Unlike T. succinifaciens, strain RCC2812T grew equally well with or without serum. Strain RCC2812T is the first commensal Treponema isolated from the human faecal microbiota of remote populations, and based on the collected data represents a novel Treponema species for which the name Treponema peruense sp. nov. is proposed. The type strain is RCC2812T (=LMG 31794T=CIP 111910T).
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Affiliation(s)
- Claire Belkhou
- Laboratory of Molecular Bacteriology, Department of Microbiology and Immunology, Rega Institute, KU Leuven, Leuven, Belgium.,Center for Microbiology, VIB, Leuven, Belgium
| | - Raul Tito Tadeo
- Laboratory of Molecular Bacteriology, Department of Microbiology and Immunology, Rega Institute, KU Leuven, Leuven, Belgium.,Center for Microbiology, VIB, Leuven, Belgium
| | - Rodrigo Bacigalupe
- Laboratory of Molecular Bacteriology, Department of Microbiology and Immunology, Rega Institute, KU Leuven, Leuven, Belgium.,Center for Microbiology, VIB, Leuven, Belgium
| | - Mireia Valles-Colomer
- Centre for Integrative Biology (CIBIO), Università degli Studi di Trento (UNITN), Trento, Italy
| | | | - Marie Joossens
- Department of Biochemistry and microbiology, Universiteit Gent, Gent, Belgium
| | - Alexandra Obregon
- Department of Genetic Counseling, College of Health Professions, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - Luis Marín Reyes
- Centro Nacional de Salud Publica, Instituto Nacional de Salud, Lima, Peru
| | - Omar Trujillo
- Centro Nacional de Salud Intercultural, Instituto Nacional de Salud, Lima, Peru
| | - Geert R B Huys
- Laboratory of Molecular Bacteriology, Department of Microbiology and Immunology, Rega Institute, KU Leuven, Leuven, Belgium.,Center for Microbiology, VIB, Leuven, Belgium
| | - Jeroen Raes
- Laboratory of Molecular Bacteriology, Department of Microbiology and Immunology, Rega Institute, KU Leuven, Leuven, Belgium.,Center for Microbiology, VIB, Leuven, Belgium
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Belkacemi S, Tidjani Alou M, Khelaifia S, Raoult D. A review of in vitro attempts to develop the axenic culture of Treponema pallidum and genomics-based suggestions to achieve this elusive goal. J Med Microbiol 2021; 70. [PMID: 34328411 DOI: 10.1099/jmm.0.001388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
To date, the axenic culture of Treponema pallidum remains a challenge in the field of microbiology despite countless attempts. Here, we conducted a comprehensive bibliographic analysis using several databases and search engines, namely Pubmed, Google scholar, Google, Web of Science and Scopus. Numerous unsuccessful empiric studies have been conducted and evaluated using as criteria dark-field microscopic observation of motile spiral shaped cells in the culture and virulence of the culture through rabbit infectivity. All of these studies failed to induce rabbit infectivity, even when deemed positive after microscopic observation leading to the misnomer of avirulent T. pallidum. In fact, this criterion was improperly chosen because not all spiral shaped cells are T. pallidum. However, these studies led to the formulation of culture media particularly favourable to the growth of several species of Treponema, including Oral Microbiology and Immunology, Zürich medium (OMIZ), Oral Treponeme Enrichment Broth (OTEB) and T-Raoult, thus allowing the increase in the number of cultivable strains of Treponema. The predicted metabolic capacities of T. pallidum show limited metabolism, also exhibited by other non-cultured and pathogenic Treponema species, in contrast to cultured Treponema species. The advent of next generation sequencing represents a turning point in this field, as the knowledge inferred from the genome can finally lead to the axenic culture of T. pallidum.
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Affiliation(s)
- Souad Belkacemi
- Aix-Marseille Univ, IRD, APHM, MEPHI, Marseille, France.,Institut Hospitalo-Universitaire Méditerranée Infection 19-21 Boulevard Jean Moulin 13005, Marseille, France
| | - Maryam Tidjani Alou
- Aix-Marseille Univ, IRD, APHM, MEPHI, Marseille, France.,Institut Hospitalo-Universitaire Méditerranée Infection 19-21 Boulevard Jean Moulin 13005, Marseille, France
| | - Saber Khelaifia
- Institut Hospitalo-Universitaire Méditerranée Infection 19-21 Boulevard Jean Moulin 13005, Marseille, France
| | - Didier Raoult
- Aix-Marseille Univ, IRD, APHM, MEPHI, Marseille, France.,Institut Hospitalo-Universitaire Méditerranée Infection 19-21 Boulevard Jean Moulin 13005, Marseille, France
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5
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Hördt A, López MG, Meier-Kolthoff JP, Schleuning M, Weinhold LM, Tindall BJ, Gronow S, Kyrpides NC, Woyke T, Göker M. Analysis of 1,000+ Type-Strain Genomes Substantially Improves Taxonomic Classification of Alphaproteobacteria. Front Microbiol 2020; 11:468. [PMID: 32373076 PMCID: PMC7179689 DOI: 10.3389/fmicb.2020.00468] [Citation(s) in RCA: 223] [Impact Index Per Article: 55.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Accepted: 03/04/2020] [Indexed: 11/13/2022] Open
Abstract
The class Alphaproteobacteria is comprised of a diverse assemblage of Gram-negative bacteria that includes organisms of varying morphologies, physiologies and habitat preferences many of which are of clinical and ecological importance. Alphaproteobacteria classification has proved to be difficult, not least when taxonomic decisions rested heavily on a limited number of phenotypic features and interpretation of poorly resolved 16S rRNA gene trees. Despite progress in recent years regarding the classification of bacteria assigned to the class, there remains a need to further clarify taxonomic relationships. Here, draft genome sequences of a collection of genomes of more than 1000 Alphaproteobacteria and outgroup type strains were used to infer phylogenetic trees from genome-scale data using the principles drawn from phylogenetic systematics. The majority of taxa were found to be monophyletic but several orders, families and genera, including taxa recognized as problematic long ago but also quite recent taxa, as well as a few species were shown to be in need of revision. According proposals are made for the recognition of new orders, families and genera, as well as the transfer of a variety of species to other genera and of a variety of genera to other families. In addition, emended descriptions are given for many species mainly involving information on DNA G+C content and (approximate) genome size, both of which are confirmed as valuable taxonomic markers. Similarly, analysis of the gene content was shown to provide valuable taxonomic insights in the class. Significant incongruities between 16S rRNA gene and whole genome trees were not found in the class. The incongruities that became obvious when comparing the results of the present study with existing classifications appeared to be caused mainly by insufficiently resolved 16S rRNA gene trees or incomplete taxon sampling. Another probable cause of misclassifications in the past is the partially low overall fit of phenotypic characters to the sequence-based tree. Even though a significant degree of phylogenetic conservation was detected in all characters investigated, the overall fit to the tree varied considerably.
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Affiliation(s)
- Anton Hördt
- Department of Bioinformatics, Leibniz Institute DSMZ – German Collection of Microorganisms and Cell Cultures, Brunswick, Germany
| | - Marina García López
- Department of Bioinformatics, Leibniz Institute DSMZ – German Collection of Microorganisms and Cell Cultures, Brunswick, Germany
| | - Jan P. Meier-Kolthoff
- Department of Bioinformatics, Leibniz Institute DSMZ – German Collection of Microorganisms and Cell Cultures, Brunswick, Germany
| | - Marcel Schleuning
- Department of Bioinformatics, Leibniz Institute DSMZ – German Collection of Microorganisms and Cell Cultures, Brunswick, Germany
| | - Lisa-Maria Weinhold
- Department of Bioinformatics, Leibniz Institute DSMZ – German Collection of Microorganisms and Cell Cultures, Brunswick, Germany
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Prague, Czechia
| | - Brian J. Tindall
- Department of Microorganisms, Leibniz Institute DSMZ – German Collection of Microorganisms and Cell Cultures, Brunswick, Germany
| | - Sabine Gronow
- Department of Microorganisms, Leibniz Institute DSMZ – German Collection of Microorganisms and Cell Cultures, Brunswick, Germany
| | - Nikos C. Kyrpides
- Department of Energy, Joint Genome Institute, Berkeley, CA, United States
| | - Tanja Woyke
- Department of Energy, Joint Genome Institute, Berkeley, CA, United States
| | - Markus Göker
- Department of Bioinformatics, Leibniz Institute DSMZ – German Collection of Microorganisms and Cell Cultures, Brunswick, Germany
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Belkacemi S, Bou Khalil J, Ominami Y, Hisada A, Fontanini A, Caputo A, Levasseur A, Lagier JC, Khelaifia S, Raoult D. Passive Filtration, Rapid Scanning Electron Microscopy, and Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry for Treponema Culture and Identification from the Oral Cavity. J Clin Microbiol 2019; 57:e00517-19. [PMID: 31340994 PMCID: PMC6760945 DOI: 10.1128/jcm.00517-19] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Accepted: 07/19/2019] [Indexed: 12/20/2022] Open
Abstract
We present here a new passive-filtration-based culture device combined with rapid identification with a new electron microscope (Hitachi TM4000) for the detection and culture of Treponema species from the human oral cavity. Of the 44 oral samples cultivated, 15 (34%) were found to be positive for Treponema using electron microscopy and were also culture positive. All were subcultured on agar plates; based on genome sequencing and analyses, 10 were strains of Treponema pectinovorum and 5 were strains of Treponema denticola The 29 samples that were negative for Treponema remained culture negative. In addition, 14 Treponema species ordered from the DSMZ collection were cultured in the T-Raoult culture medium optimized here. Finally, matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) was used and 30 novel spectra were added to the MALDI-TOF MS database. We have successfully developed a new and effective method for treponemal detection, culture, and identification.
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Affiliation(s)
- Souad Belkacemi
- Microbes Evolution Phylogeny, and Infections, Aix-Marseille Université, Institut de Recherche pour le Développement, Assistance Publique-Hopitaux de Marseille, Marseille, France
- Institut Hospitalo-Universitaire Méditerranée Infection, Marseille, France
| | - Jacques Bou Khalil
- Microbes Evolution Phylogeny, and Infections, Aix-Marseille Université, Institut de Recherche pour le Développement, Assistance Publique-Hopitaux de Marseille, Marseille, France
- Institut Hospitalo-Universitaire Méditerranée Infection, Marseille, France
| | - Yusuke Ominami
- Science and Medical Systems Business Group, Hitachi High-Technologies Corp., Tokyo, Japan
| | - Akiko Hisada
- Research and Development Group, Hitachi, Ltd., Saitama, Japan
| | - Anthony Fontanini
- Institut Hospitalo-Universitaire Méditerranée Infection, Marseille, France
| | - Aurelia Caputo
- Hôpital de la Timone, Assistance Publique-Hopitaux de Marseille, Marseille, France
| | - Anthony Levasseur
- UMR VITROME, Aix Marseille Université, Institut de Recherche pour le Développement, SSA, Assistance Publique-Hopitaux de Marseille, IHU-Méditerranée Infection, Marseille, France
| | - Jean-Christophe Lagier
- Microbes Evolution Phylogeny, and Infections, Aix-Marseille Université, Institut de Recherche pour le Développement, Assistance Publique-Hopitaux de Marseille, Marseille, France
| | - Saber Khelaifia
- Microbes Evolution Phylogeny, and Infections, Aix-Marseille Université, Institut de Recherche pour le Développement, Assistance Publique-Hopitaux de Marseille, Marseille, France
- Institut Hospitalo-Universitaire Méditerranée Infection, Marseille, France
| | - Didier Raoult
- Microbes Evolution Phylogeny, and Infections, Aix-Marseille Université, Institut de Recherche pour le Développement, Assistance Publique-Hopitaux de Marseille, Marseille, France
- Institut Hospitalo-Universitaire Méditerranée Infection, Marseille, France
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7
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Fonkou MDM, Dufour JC, Dubourg G, Raoult D. Repertoire of bacterial species cultured from the human oral cavity and respiratory tract. Future Microbiol 2018; 13:1611-1624. [DOI: 10.2217/fmb-2018-0181] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
While the gut microbiota is currently in the spotlight, the airway microbiome has been recently associated with several pulmonary diseases and carcinogenesis. As there are several biases associated with high-throughput sequencing methods, cultivation techniques are crucial for the investigation of the human microbiome. We thus aimed to build an exhaustive database, including a list of microbes isolated by culture from respiratory specimens, by performing a review of the literature. Herein, we have listed a total of 756 species cultured from the human respiratory tract. This represents 27.23% of the overall bacterial richness captured from human being by culture methods. This repertoire could be valuable for the elucidation of the interactions between the respiratory microbiome and human health.
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Affiliation(s)
- Maxime DM Fonkou
- Aix Marseille Univ., IRD, MEPHI, IHU Méditerranée Infection, Marseille, France
| | - Jean-Charles Dufour
- Aix Marseille Univ., INSERM, IRD, SESSTIM, Sciences Economiques & Sociales de la Santé & Traitement de l'Information Médicale, Marseille, France
- APHM, Hôpital de la Timone, Service Biostatistique et Technologies de l'Information et de la Communication, Marseille, France
| | - Grégory Dubourg
- Aix Marseille Univ., IRD, MEPHI, IHU Méditerranée Infection, Marseille, France
| | - Didier Raoult
- Aix Marseille Univ., IRD, MEPHI, IHU Méditerranée Infection, Marseille, France
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8
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The occurrence of Treponema spp. in gingival plaque from dogs with varying degree of periodontal disease. PLoS One 2018; 13:e0201888. [PMID: 30092089 PMCID: PMC6084996 DOI: 10.1371/journal.pone.0201888] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Accepted: 07/24/2018] [Indexed: 11/29/2022] Open
Abstract
Periodontal disease is common in dogs and is initiated by gingival plaque composed of several hundred bacterial species. Some of these species have specifically been pointed out as potential periodontal pathogens, such as Treponema spp. Treponema spp. are difficult to culture and therefore the majority have been detected by culture-independent methods, such as PCR (Polymerase Chain Reaction). This leaves many Treponema spp. uncharacterized and unnamed. In this study, treponemes were investigated in gingival plaque from dogs with varying degree of periodontal disease with the aim to describe their occurrence and diversity in dogs. The methods used were culture, phase-contrast microscopy, PCR targeting the 16SrRNA-tRNAIle intergenic spacer region (ISR2), sequencing of the ISR2 and phylogenetic analysis. Treponema spp. were detected in samples from 10 out of 11 dogs and isolates were obtained from six dogs. Both healthy and periodontitis affected dogs were Treponema positive. Phylogenetic analysis, based on ISR2 sequences, revealed a large diversity of treponemes in the study population that were found to be distributed mainly in two groups, corresponding to the human oral treponeme phylogroups II (Treponema denticola) and IV (Treponema maltophilum) genetic groups. They were generally more distantly related to other treponemes in these groups. Treponemes from dogs with periodontitis and dogs with mild gingivitis without periodontitis did not differ in any obvious way. The results indicate that several phylotypes of oral treponemes are common in dogs regardless of periodontal status.
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Staton GJ, Newbrook K, Clegg SR, Birtles RJ, Evans NJ, Carter SD. Treponema rectale sp. nov., a spirochete isolated from the bovine rectum. Int J Syst Evol Microbiol 2017; 67:2470-2475. [DOI: 10.1099/ijsem.0.002051] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Gareth J. Staton
- Department of Infection Biology, Institute of Infection and Global Health, University of Liverpool, iC2 Building, Liverpool Science Park, Brownlow Hill, Liverpool, L3 5RF, UK
| | - Kerry Newbrook
- Department of Infection Biology, Institute of Infection and Global Health, University of Liverpool, iC2 Building, Liverpool Science Park, Brownlow Hill, Liverpool, L3 5RF, UK
| | - Simon R. Clegg
- Department of Infection Biology, Institute of Infection and Global Health, University of Liverpool, iC2 Building, Liverpool Science Park, Brownlow Hill, Liverpool, L3 5RF, UK
| | - Richard J. Birtles
- School of Environment and Life Sciences, Peel Building, University of Salford, Salford, M5 4WT, UK
| | - Nicholas J. Evans
- Department of Infection Biology, Institute of Infection and Global Health, University of Liverpool, iC2 Building, Liverpool Science Park, Brownlow Hill, Liverpool, L3 5RF, UK
| | - Stuart D. Carter
- Department of Infection Biology, Institute of Infection and Global Health, University of Liverpool, iC2 Building, Liverpool Science Park, Brownlow Hill, Liverpool, L3 5RF, UK
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Newbrook K, Staton GJ, Clegg SR, Birtles RJ, Carter SD, Evans NJ. Treponema ruminis sp. nov., a spirochaete isolated from the bovine rumen. Int J Syst Evol Microbiol 2017; 67:1349-1354. [DOI: 10.1099/ijsem.0.001812] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Kerry Newbrook
- Department of Infection Biology, Institute of Infection and Global Health, University of Liverpool, Liverpool Science Park Innovation Centre 2, 146 Brownlow Hill, Liverpool, UK
| | - Gareth J Staton
- Department of Infection Biology, Institute of Infection and Global Health, University of Liverpool, Liverpool Science Park Innovation Centre 2, 146 Brownlow Hill, Liverpool, UK
| | - Simon R Clegg
- Department of Infection Biology, Institute of Infection and Global Health, University of Liverpool, Liverpool Science Park Innovation Centre 2, 146 Brownlow Hill, Liverpool, UK
| | - Richard J Birtles
- School of Environment and Life Sciences, University of Salford, Greater Manchester, UK
| | - Stuart D Carter
- Department of Infection Biology, Institute of Infection and Global Health, University of Liverpool, Liverpool Science Park Innovation Centre 2, 146 Brownlow Hill, Liverpool, UK
| | - Nicholas J Evans
- Department of Infection Biology, Institute of Infection and Global Health, University of Liverpool, Liverpool Science Park Innovation Centre 2, 146 Brownlow Hill, Liverpool, UK
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Multilocus Sequence Analysis of Phylogroup 1 and 2 Oral Treponeme Strains. Appl Environ Microbiol 2017; 83:AEM.02499-16. [PMID: 27864174 DOI: 10.1128/aem.02499-16] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Accepted: 11/14/2016] [Indexed: 02/08/2023] Open
Abstract
More than 75 "species-level" phylotypes of spirochete bacteria belonging to the genus Treponema reside within the human oral cavity. The majority of these oral treponeme phylotypes correspond to as-yet-uncultivated taxa or strains of uncertain standing in taxonomy. Here, we analyze phylogenetic and taxonomic relationships between oral treponeme strains using a multilocus sequence analysis (MLSA) scheme based on the highly conserved 16S rRNA, pyrH, recA, and flaA genes. We utilized this MLSA scheme to analyze genetic data from a curated collection of oral treponeme strains (n = 71) of diverse geographical origins. This comprises phylogroup 1 (n = 23) and phylogroup 2 (n = 48) treponeme strains, including all relevant American Type Culture Collection reference strains. The taxonomy of all strains was confirmed or inferred via the analysis of ca. 1,450-bp 16S rRNA gene sequences using a combination of bioinformatic and phylogenetic approaches. Taxonomic and phylogenetic relationships between the respective treponeme strains were further investigated by analyzing individual and concatenated flaA (1,074-nucleotide [nt]), recA (1,377-nt), and pyrH (696-nt) gene sequence data sets. Our data confirmed the species differentiation between Treponema denticola (n = 41) and Treponema putidum (n = 7) strains. Notably, our results clearly supported the differentiation of the 23 phylogroup 1 treponeme strains into five distinct "species-level" phylotypes. These respectively corresponded to "Treponema vincentii" (n = 11), Treponema medium (n = 1), "Treponema sinensis" (Treponema sp. IA; n = 4), Treponema sp. IB (n = 3), and Treponema sp. IC (n = 4). In conclusion, our MLSA-based approach can be used to effectively discriminate oral treponeme taxa, confirm taxonomic assignment, and enable the delineation of species boundaries with high confidence. IMPORTANCE Periodontal diseases are caused by persistent polymicrobial biofilm infections of the gums and underlying tooth-supporting structures and have a complex and variable etiology. Although Treponema denticola is strongly associated with periodontal diseases, the etiological roles of other treponeme species/phylotypes are less well defined. This is due to a paucity of formal species descriptions and a poor understanding of genetic relationships between oral treponeme taxa. Our study directly addresses these issues. It represents one of the most comprehensive analyses of oral treponeme strains performed to date, including isolates from North America, Europe, and Asia. We envisage that our results will greatly facilitate future metagenomic efforts aimed at characterizing the clinical distributions of oral treponeme species/phylotypes, helping investigators to establish a more detailed understanding of their etiological roles in periodontal diseases and other infectious diseases. Our results are also directly relevant to various polymicrobial tissue infections in animals, which also involve treponeme populations.
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Hiranmayi KV, Sirisha K, Ramoji Rao MV, Sudhakar P. Novel Pathogens in Periodontal Microbiology. J Pharm Bioallied Sci 2017; 9:155-163. [PMID: 28979069 PMCID: PMC5621177 DOI: 10.4103/jpbs.jpbs_288_16] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Periodontitis is a polymicrobial disease caused by complex interactions between distinct pathogens in a biofilm resulting in the destruction of periodontal tissues. It seems evident that unknown microorganisms might be involved in onset or progression of periodontitis. For many decades, research in the field of oral microbiology failed to identify certain subgingival microbiota due to technical limitations but, over a period of 12 years using molecular approaches and sequencing techniques, it became feasible to reveal the existence of new periodontal pathogens. Therefore, it is evident that in addition to conventional periodontal pathogens, other microbes might be involved in onset and progression of periodontitis. The novel pathogens enlisted under periodontal phylogeny include Cryptobacterium curtum, Dialister pneumosintes, Filifactor alocis, Mitsuokella dentalis, Slackia exigua, Selenomonas sputigena, Solobacterium moorei, Treponema lecithinolyticum, and Synergistes. The polymicrobial etiology of periodontitis has been elucidated by comprehensive techniques, and studies throwing light on the possible virulence mechanisms possessed by these novel periodontal pathogens are enlisted.
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Affiliation(s)
- K Vidya Hiranmayi
- Post Graduate Student, Department of Periodontics and Implantology, Drs S and NR Siddhartha Institute of Dental Sciences, Krishna District, Andhra Pradesh, India
| | - K Sirisha
- Reader, Department of Periodontics and Implantology, Drs S and NR Siddhartha Institute of Dental Sciences, Krishna District, Andhra Pradesh, India
| | - M V Ramoji Rao
- HOD, Department of Periodontics and Implantology, Drs S and NR Siddhartha Institute of Dental Sciences, Krishna District, Andhra Pradesh, India
| | - P Sudhakar
- Post Graduate Student, Department of Periodontics and Implantology, Drs S and NR Siddhartha Institute of Dental Sciences, Krishna District, Andhra Pradesh, India
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You M, Mo S, Leung WK, Watt RM. Comparative analysis of oral treponemes associated with periodontal health and disease. BMC Infect Dis 2013; 13:174. [PMID: 23578286 PMCID: PMC3637317 DOI: 10.1186/1471-2334-13-174] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2012] [Accepted: 03/27/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Periodontal diseases, such as periodontitis, are chronic inflammatory infections affecting the gingivae (gums), underlying connective tissues and bone that support the teeth. Oral treponemes (genus Treponema) are widely-considered to play important roles in periodontal disease etiology and pathogenesis; however, precise relationships remain to be fully established. METHODS A 16S rRNA clone library-based approach was used to comprehensively characterize and compare the diversity of treponeme taxa present in subgingival plaque sampled from periodontitis patients (n = 10) versus periodontitis-free controls (n = 10). 16S rRNA gene sequences were assigned to operational taxonomic units (OTUs) using a 99% identity cut-off A variety of taxonomy (OTU) and phylogeny-based statistical approaches were used to compare populations of treponeme OTUs present in both subject groups. RESULTS A total of 615 plasmid clones containing ca. 1500 bp Treponema 16S rRNA gene sequences were obtained; 365 from periodontitis subjects, 250 from periodontitis-free controls. These were assigned to 110 treponeme OTUs. 93 OTUs were detected in the periodontitis subjects (mean 9.3 ± 5.2 OTUs per subject; range 9-26), and 43 OTUs were detected in controls (mean 4.3 ± 5.9 OTUs per subject; range 3-20). OTUs belonging to oral treponeme phylogroups 1-7 were detected in both subject sets. Phylogroup 1 treponemes had the highest levels of OTU richness (diversity) and clonal abundance within both subject groups. Levels of OTU richness and clonal abundance of phylogroup 2 treponemes were significantly higher in the periodontitis subjects (Mann Whitney U-test, p < 0.001). Both OTU-based and phylogeny-based analyses clearly indicated that there were significant differences in the composition of treponeme communities present in periodontitis versus control subjects. The detection frequency of five OTUs showed a statistically-significant correlation with disease status. The OTU (8P47) that corresponded to the type strain of Treponema denticola had the strongest association with periodontitis (p < 0.01). CONCLUSIONS Higher levels of treponeme taxon richness and clonal abundance were associated with periodontitis. However, our results clearly indicated that subjects free from clinical symptoms of periodontal disease also contained highly diverse populations of treponeme bacteria within their subgingival microbiota. Our data supports the hypothesis that specific treponeme taxa are associated with periodontal disease.
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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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Visser M, Ellen R. New insights into the emerging role of oral spirochaetes in periodontal disease. Clin Microbiol Infect 2011; 17:502-12. [DOI: 10.1111/j.1469-0691.2011.03460.x] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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16
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Goller KV, Fyumagwa RD, Nikolin V, East ML, Kilewo M, Speck S, Müller T, Matzke M, Wibbelt G. Fatal canine distemper infection in a pack of African wild dogs in the Serengeti ecosystem, Tanzania. Vet Microbiol 2010; 146:245-52. [DOI: 10.1016/j.vetmic.2010.05.018] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2010] [Revised: 05/03/2010] [Accepted: 05/05/2010] [Indexed: 11/28/2022]
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Parahitiyawa NB, Scully C, Leung WK, Yam WC, Jin LJ, Samaranayake LP. Exploring the oral bacterial flora: current status and future directions. Oral Dis 2009; 16:136-45. [PMID: 19627515 DOI: 10.1111/j.1601-0825.2009.01607.x] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
OBJECTIVE The oral cavity forms an indispensable part of the human microbiome, for its unique and diverse microflora distributed within various niches. While majority of these organisms exhibit commensalism, shifts in bacterial community dynamics cause pathological changes within oral cavity and distant sites. The aim of this review was to appraise the current and emerging methods of detecting bacteria of the oral cavity paying particular attention to the cultivation independent methods. DESIGN Literature pertaining to cultivation based and cultivation independent methods of oral bacterial identification was reviewed. METHODS The specific advantages and disadvantages of cultivation based, microscopic, immunological and metagenomic identification methods were appraised. RESULTS Because of their fastidious and exacting growth requirements, cultivation based studies grossly underestimate the extent of bacterial diversity in these polymicrobial infections. Culture independent methods deemed more sensitive in identifying difficult to culture and novel bacterial species. CONCLUSION Apart from characterizing potentially novel bacterial species, the nucleic acid sequence data analyzed using various bioinformatics protocols have revealed that there are in excess of 700 bacterial species inhabiting the mouth. Moreover, the latest pyrosequencing based methods have further broadened the extent of bacterial diversity in oral niches.
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Affiliation(s)
- N B Parahitiyawa
- Oral Biosciences, Faculty of Dentistry, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong (SAR), China
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Fenno JC. Laboratory maintenance of Treponema denticola. CURRENT PROTOCOLS IN MICROBIOLOGY 2008; Chapter 12:Unit 12B.1. [PMID: 18770551 DOI: 10.1002/9780471729259.mc12b01s00] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
This unit describes the methods, media, and equipment necessary for routine laboratory culture and handling of the anaerobic oral spirochete Treponema denticola. Topics discussed include nutrient requirements, recommended media formulations, and expected growth kinetics, as well as methods and equipment necessary to maintain anaerobic conditions. An additional protocol on isolation of T. denticola from clinical samples is included.
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Schröder NW, Eckert J, Stübs G, Schumann RR. Immune responses induced by spirochetal outer membrane lipoproteins and glycolipids. Immunobiology 2008; 213:329-40. [DOI: 10.1016/j.imbio.2007.11.003] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2007] [Revised: 10/18/2007] [Accepted: 11/01/2007] [Indexed: 02/06/2023]
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Highly conserved surface proteins of oral spirochetes as adhesins and potent inducers of proinflammatory and osteoclastogenic factors. Infect Immun 2008; 76:2428-38. [PMID: 18390996 DOI: 10.1128/iai.01128-07] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Oral spirochetes include enormously heterogeneous Treponema species, and some have been implicated in the etiology of periodontitis. In this study, we characterized highly conserved surface proteins in four representative oral spirochetes (Treponema denticola, T. lecithinolyticum, T. maltophilum, and T. socranskii subsp. socranskii) that are homologs of T. pallidum Tp92, with opsonophagocytic potential and protective capacity against syphilis. Tp92 homologs of oral spirochetes had predicted signal peptides (20 to 31 amino acids) and molecular masses of 88 to 92 kDa for mature proteins. They showed amino acid sequence identities of 37.9 to 49.3% and similarities of 54.5 to 66.9% to Tp92. The sequence identities and similarities of Tp92 homologs of oral treponemes to one another were 41.6 to 71.6% and 59.9 to 85.6%, respectively. The tp92 gene homologs were successfully expressed in Escherichia coli, and the recombinant proteins were capable of binding to KB cells, an epithelial cell line, and inhibited the binding of the whole bacteria to the cells. Antiserum (the immunoglobulin G fraction) raised against a recombinant form of the T. denticola Tp92 homolog cross-reacted with homologs from three other species of treponemes. The Tp92 homologs stimulated various factors involved in inflammation and osteoclastogenesis, like interleukin-1beta (IL-1beta), tumor necrosis factor alpha, IL-6, prostaglandin E(2), and matrix metalloproteinase 9, in host cells like monocytes and fibroblasts. Our results demonstrate that Tp92 homologs of oral spirochetes are highly conserved and may play an important role in cell attachment, inflammation, and tissue destruction. The coexistence of various Treponema species in a single periodontal pocket and, therefore, the accumulation of multiple Tp92 homologs may amplify the pathological effect in periodontitis.
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Speck S, Höner OP, Wachter B, Fickel J. Characterization of Streptococcus equi subsp. ruminatorum isolated from spotted hyenas (Crocuta crocuta) and plains zebras (Equus burchelli), and identification of a M-like protein (SrM) encoding gene. Vet Microbiol 2008; 128:148-59. [DOI: 10.1016/j.vetmic.2007.09.019] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2007] [Revised: 09/18/2007] [Accepted: 09/26/2007] [Indexed: 10/22/2022]
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Lee HR, Choi BK. Identification of a fibronectin-binding protein of Treponema lecithinolyticum by two-dimensional gel electrophoresis and ligand binding assay. Can J Microbiol 2007; 53:1185-90. [DOI: 10.1139/w07-086] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Treponema lecithinolyticum is associated with periodontitis and endodontic infections. As a critical early step in the infection process, fibronectin-binding protein (Fbp) is known to be involved in the adhesion of bacteria to cell surfaces for colonization and, hence, is considered to be a virulence factor. In this study, we identified an Fbp from the T. lecithinolyticum cell surface with a molecular mass of about 52 kDa by using 2-dimensional gel electrophoresis followed by a ligand binding assay. As T. lecithinolyticum is capable of binding to soluble and immobilized fibronectin, this Fbp may contribute to bacterial attachment to host cells.
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Affiliation(s)
- Hae-Ri Lee
- Department of Oral Microbiology and Immunology, 28 Yongon-Dong, Chongno-Gu, Seoul 110-749, Republic of Korea
- Dental Research Institute, School of Dentistry, Seoul National University, 28 Yongon-Dong, Chongno-Gu, Seoul 110-749, Republic of Korea
| | - Bong-Kyu Choi
- Department of Oral Microbiology and Immunology, 28 Yongon-Dong, Chongno-Gu, Seoul 110-749, Republic of Korea
- Dental Research Institute, School of Dentistry, Seoul National University, 28 Yongon-Dong, Chongno-Gu, Seoul 110-749, Republic of Korea
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Haffajee AD, Teles RP, Socransky SS. Association of Eubacterium nodatum and Treponema denticola with human periodontitis lesions. ACTA ACUST UNITED AC 2006; 21:269-82. [PMID: 16922925 DOI: 10.1111/j.1399-302x.2006.00287.x] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND The purpose of the present investigation was to compare the levels, proportions and percentage of sites colonized by 40 bacterial species in subgingival plaque samples from periodontally healthy subjects and patients with chronic periodontitis to seek possible pathogens other than the consensus pathogens Porphyromonas gingivalis and Tannerella forsythia. METHOD Subgingival plaque samples were taken from the mesial aspect of each tooth in 635 subjects with chronic periodontitis and 189 periodontally healthy subjects. The samples were individually analyzed for their content of 40 bacterial species using checkerboard DNA-DNA hybridization (total samples = 21,832). Mean counts, % DNA probe counts and percentage of sites colonized at >10(5) were determined for each species in each subject and then averaged in each clinical group. Significance of difference between groups was determined using the Mann-Whitney test. Association between combinations of species and periodontal status was examined by stepwise logistic regression analysis. Analyses were repeated using a subset of subjects from both clinical groups who had proportions of P. gingivalis plus T. forsythia less than the median (4.42%) found in periodontally healthy subjects. All analyses were adjusted for multiple comparisons. RESULTS For the 824 subjects the consensus pathogens P. gingivalis and T. forsythia as well as Eubacterium nodatum and Treponema denticola had significantly higher mean counts, proportions and percentage of sites colonized in samples from subjects with periodontitis than from periodontally healthy subjects. There were significantly more Capnocytophaga gingivalis, Streptococcus gordonii and Veillonella parvula in periodontally healthy subjects. E. nodatum, T. denticola, Streptococcus oralis, Streptococcus intermedius, Fusobacterium nucleatum ssp. vincentii all had higher counts and proportions in diseased than healthy subjects who had low proportions of P. gingivalis and T. forsythia. Logistic regression analysis indicated that the same species groups were associated with disease status after adjusting for the proportions of the other species. CONCLUSIONS This investigation confirmed the strong association of P. gingivalis and T. forsythia with chronic periodontitis and emphasized a strong association of E. nodatum and T. denticola with periodontitis whether in the presence or absence of high levels of the consensus pathogens. Other species, including S. oralis, Eikenella corrodens, S. intermedius and F. nucleatum ssp. vincentii, were associated with disease when P. gingivalis and T. forsythia were present in low proportions.
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Affiliation(s)
- A D Haffajee
- Department of Periodontology, The Forsyth Institute, 140 The Fenway, Boston, MA 02115, USA.
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Clark DT, Soory M. The metabolism of cholesterol and certain hormonal steroids by Treponema denticola. Steroids 2006; 71:352-63. [PMID: 16436288 DOI: 10.1016/j.steroids.2005.11.006] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2005] [Revised: 11/02/2005] [Accepted: 11/17/2005] [Indexed: 11/23/2022]
Abstract
The aim was to investigate whether reference cultures and fresh isolates of Treponema denticola are able to 5alpha-reduce and further metabolise testosterone, 4-androstenedione, progesterone, corticosterone, cortisol or cholesterol. Two reference and five freshly isolated cultures of T. denticola were incubated with either radiolabeled or unlabeled steroid substrates; in the first case products were identified by thin layer chromatography and in the latter by gas chromatography-mass spectroscopy. All the substrates were 5alpha-reduced. Both reference cultures and fresh isolates of T. denticola presented 3beta- and 17beta-hydroxy steroid dehydrogenase activity. It was concluded that T. denticola was capable of steroid metabolism and hypotheses are discussed regarding the in vivo function of this metabolism including, T. denticola utilising host supplied steroids as growth factors and T. denticola steroid metabolism acting as a virulence factor.
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Affiliation(s)
- Douglas T Clark
- Department of Microbiology, King's College London Dental Institute at Guy's, King's College and St. Thomas' Hospitals, UK.
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Lehnen A, Busse HJ, Frölich K, Krasinska M, Kämpfer P, Speck S. Arcanobacterium bialowiezense sp. nov. and Arcanobacterium bonasi sp. nov., isolated from the prepuce of European bison bulls (Bison bonasus) suffering from balanoposthitis, and emended description of the genus Arcanobacterium Collins et al. 1983. Int J Syst Evol Microbiol 2006; 56:861-866. [PMID: 16585707 DOI: 10.1099/ijs.0.63923-0] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A taxonomic study was performed on 13 bacterial strains isolated from preputial swabs of European bison (Bison bonasus) bulls suffering from balanoposthitis. The isolates were Gram-positive, non-motile, facultatively anaerobic, diphtheroid-shaped cells. Based on biochemical profiles and BOX-PCR-generated genomic fingerprints, the isolates were grouped into two clusters represented by four and nine strains, respectively. Strains 1(W3/01)T and 2(W106/04)T, selected as representatives of the two clusters, shared 97·2 % 16S rRNA gene sequence similarity. The highest gene sequence similarities found (95·5–96·4 %) were to Arcanobacterium pyogenes DSM 20630T and Arcanobacterium bernardiae DSM 9152T, demonstrating that the novel strains are members of the genus Arcanobacterium, but are not members of a recognized species. The polar lipid profiles of the two novel strains displayed the major characteristics also found in A. pyogenes DSM 20630T and Arcanobacterium haemolyticum DSM 20595T. Detection of a quinone system with MK-10(H4) as the predominant compound confirmed phylogenetic relatedness of the novel strains to A. pyogenes and separated them from the type species of the genus, A. haemolyticum, which contains MK-9(H4) as the predominant quinone. Results from DNA–DNA hybridizations clearly demonstrated that strains 1(W3/01)T and 2(W106/04)T represent separate species. Based on these data, two novel species of the genus Arcanobacterium are described, for which the names Arcanobacterium bialowiezense sp. nov. [type strain 1(W3/01)T=DSM 17162T=NCTC 13354T] and Arcanobacterium bonasi sp. nov. [type strain 2(W106/04)T=DSM 17163T=NCTC 13355T] are proposed.
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Affiliation(s)
- Alexandra Lehnen
- Institut für Zoo- und Wildtierforschung, Alfred-Kowalke-Str.17, D-10315 Berlin, Germany
| | - Hans-Jürgen Busse
- Institut für Bakteriologie, Mykologie und Hygiene, Veterinärmedizinische Universität, Veterinärplatz 1, 1210 Wien, Austria
| | - Kai Frölich
- Institut für Zoo- und Wildtierforschung, Alfred-Kowalke-Str.17, D-10315 Berlin, Germany
| | | | - Peter Kämpfer
- Institut für Angewandte Mikrobiologie, Justus-Liebig-Universität, Heinrich Buff-Ring 26-32 (IFZ), D-35392 Giessen, Germany
| | - Stephanie Speck
- Institut für Zoo- und Wildtierforschung, Alfred-Kowalke-Str.17, D-10315 Berlin, Germany
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Nordhoff M, Taras D, Macha M, Tedin K, Busse HJ, Wieler LH. Treponema berlinense sp. nov. and Treponema porcinum sp. nov., novel spirochaetes isolated from porcine faeces. Int J Syst Evol Microbiol 2005; 55:1675-1680. [PMID: 16014500 DOI: 10.1099/ijs.0.63388-0] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Limit-dilution procedures were used to isolate seven, helically coiled bacterial strains from faeces of swine that constituted two unidentified taxa. Comparative 16S rRNA gene sequence analysis showed highest similarity values with species of the genus Treponema indicating that the isolates are members of this genus. Strain 7CPL208(T), as well as five further isolates, and 14V28(T) displayed the highest 16S rRNA gene sequence similarities with Treponema pectinovorum ATCC 33768(T) (92.3%) and Treponema parvum OMZ 833(T) (89.9%), respectively. Polar lipid profiles distinguished 7CPL208(T) and 14V28(T) from each other as well as from related species. Based on their phenotypic and genotypic distinctiveness, strains 7CPL208(T) and 14V28(T) are suggested to represent two novel species of the genus Treponema, for which the names Treponema berlinense sp. nov. and Treponema porcinum sp. nov. are proposed. The type strain for Treponema berlinense is 7CPL208(T) (=ATCC BAA-909(T)=CIP 108244(T)=JCM 12341(T)) and for Treponema porcinum 14V28(T) (=ATCC BAA-908(T)=CIP 108245(T)=JCM 12342(T)).
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Affiliation(s)
- Marcel Nordhoff
- Institut für Mikrobiologie und Tierseuchen, Freie Universität Berlin, D-10115 Berlin, Germany
| | - David Taras
- Institut für Tierernährung, Freie Universität Berlin, D-10115 Berlin, Germany
| | - Moritz Macha
- Institut für Tierernährung, Freie Universität Berlin, D-10115 Berlin, Germany
| | - Karsten Tedin
- Institut für Mikrobiologie und Tierseuchen, Freie Universität Berlin, D-10115 Berlin, Germany
| | - Hans-Jürgen Busse
- Institut für Bakteriologie, Mykologie und Hygiene, Veterinärmedizinische Universität, A-1210 Wien, Austria
| | - Lothar H Wieler
- Institut für Mikrobiologie und Tierseuchen, Freie Universität Berlin, D-10115 Berlin, Germany
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Voigt CC, Caspers B, Speck S. BATS, BACTERIA, AND BAT SMELL: SEX-SPECIFIC DIVERSITY OF MICROBES IN A SEXUALLY SELECTED SCENT ORGAN. J Mammal 2005. [DOI: 10.1644/1545-1542(2005)086[0745:bbabss]2.0.co;2] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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Wyss C, Dewhirst FE, Paster BJ, Thurnheer T, Luginbühl A. Guggenheimella bovis gen. nov., sp. nov., isolated from lesions of bovine dermatitis digitalis. Int J Syst Evol Microbiol 2005; 55:667-671. [PMID: 15774641 DOI: 10.1099/ijs.0.63116-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Dermatitis digitalis is an economically important ulcerative disease of undetermined aetiology affecting the hooves of cattle. Material was examined from two independent cases of this disease in Switzerland. Cultures from the advancing front of both lesions yielded large numbers of closely related short, mesophilic, non-motile, non-spore-forming, anaerobic, proteolytic, Gram-positive rods. The 16S rRNA gene sequences of strains OMZ 913(T) and OMZ 915 were identical and indicate Tindallia magadiensis and Eubacterium saphenum as their closest relatives. Phenotypically, the novel isolates are clearly distinguished from related bacteria by protein and antigen patterns, by cellular fatty acids and by API ZYM activities. The diamino acid of the Gram-positive cell wall is ornithine and the G+C content of OMZ 913(T) DNA is 44.4 mol%. The phylogenetic distance from recognized taxa in the phylum Firmicutes is sufficient to place these bovine isolates into a novel genus and species, for which the name Guggenheimella bovis gen. nov., sp. nov. is proposed, with OMZ 913(T) (=CIP 108087(T)=DSM 15657(T)) as the type strain.
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Affiliation(s)
- C Wyss
- Institut für Orale Biologie, Zentrum für Zahn-, Mund- und Kieferheilkunde der Universität Zürich, Plattenstrasse 11, CH-8028 Zürich, Switzerland
| | - F E Dewhirst
- Department of Molecular Genetics, The Forsyth Institute, 140 Fenway, Boston, MA 02115, USA
| | - B J Paster
- Department of Molecular Genetics, The Forsyth Institute, 140 Fenway, Boston, MA 02115, USA
| | - T Thurnheer
- Institut für Orale Biologie, Zentrum für Zahn-, Mund- und Kieferheilkunde der Universität Zürich, Plattenstrasse 11, CH-8028 Zürich, Switzerland
| | - A Luginbühl
- Tierarztpraxis, CH-3186 Düdingen, Switzerland
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Affiliation(s)
- Richard P Ellen
- Faculty of Dentistry, University of Toronto, Toronto, Ontario, Canada
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Abstract
OBJECTIVES The application of molecular, mainly 16S ribosomal RNA (rRNA)-based approaches enables researchers to bypass the cultivation step and has proven its usefulness in studying the microbial composition in a variety of ecosystems, including the human oral cavity. In this mini-review, we describe the impact of these culture-independent approaches on our knowledge of the ecology of the human oral cavity and provide directions for future studies that should emphasize the role of specific strains, species and groups of microbes in periodontal disease. MATERIALS AND METHODS Recent findings are summarized to elucidate the relationship between periodontal disease and human oral microbiota, including as-yet-to-be-cultured organisms. RESULTS The real-time polymerase chain reaction (PCR) method was developed to detect and quantify periodontopathic bacteria, such as Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythensis (formerly Bacteroides forsythus) and Treponema denticola. The checkerboard DNA-DNA hybridization technique allowed enumeration of large numbers of species in very large numbers of samples. 16S rRNA gene clone library analysis revealed the diversity of human oral microbiota and the existence of as-yet-to-be-cultured organisms that are presumed periodontal pathogens. In addition, terminal restriction fragment length polymorphism (T-RFLP) analysis was applied for assessment of diversity of human oral microbiota. CONCLUSION Culture-independent approaches are useful for studying the microbial ecology in the human oral cavity and should be useful in the future to elucidate the etiology of periodontal disease.
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Affiliation(s)
- Mitsuo Sakamoto
- Microbe Division/Japan Collection of Microorganisms, RIKEN BioResource Center, Wako, Saitama, Japan.
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Choi BK, Moon SY, Cha JH, Kim KW, Yoo YJ. Prostaglandin E2Is a Main Mediator in Receptor Activator of Nuclear Factor-κB Ligand-Dependent Osteoclastogenesis Induced byPorphyromonas gingivalis, Treponema denticola, andTreponema socranskii. J Periodontol 2005; 76:813-20. [PMID: 15898943 DOI: 10.1902/jop.2005.76.5.813] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND Periodontitis is an inflammatory disease that often leads to destruction of alveolar bone; a number of bacteria in subgingival plaque are associated with bone destruction in periodontitis. To understand the mechanism of how periodontopathogens induce osteoclastogenesis, we determined which mediators are involved in the osteoclastogenesis. METHODS We investigated effects of sonicates from three periodontopathic bacteria, Porphyromonas gingivalis, Treponema denticola, and Treponema socranskii, on osteoclast formation in a co-culture system of mouse calvaria-derived osteoblasts and bone marrow cells. The osteoclast formation was determined by tartrate resistant acid phosphatase (TRAP) staining. The expression of the receptor activator of nuclear factor-kappa B ligand (RANKL), prostaglandin E(2) (PGE(2)) and osteoprotegerin (OPG) in mouse calvaria-derived osteoblasts was determined by immunoassay. RESULTS Each bacterial sonicate induced the osteoclast formation in the co-culture system. These bacterial sonicates increased the expression of RANKL and PGE(2), and decreased the expression of OPG in osteoblasts. The addition of OPG, an inhibitor of RANKL, in the co-culture completely suppressed the osteoclastogenesis that was stimulated by each bacterial sonicate. Indomethacin, which is an inhibitor of PGE(2) synthesis, reduced more than 88% of the osteoclast formation induced by each bacterial sonicate. Indomethacin inhibited more than 80% of RANKL expression in osteoblasts induced by T. denticola and T. socranskii, and 59% by P. gingivalis. Indomethacin completely recovered the depression of OPG expression in osteoblasts by T. denticola and T. socranskii to the level of the untreated osteoblasts. Indomethacin recovered the reduction of OPG expression by P. gingivalis to 67%. CONCLUSION These findings suggest that the osteoclastogenesis by P. gingivalis, T. denticola, and T. socranskii is mediated by a RANKL-dependent pathway and that PGE(2) is a main factor in the pathway by the enhancing of RANKL expression and the depression of osteoprotegerin, a RANKL inhibitor.
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Affiliation(s)
- Bong-Kyu Choi
- Department of Oromaxillofacial Infection and Immunity, College of Dentistry, Seoul National University, Seoul, Korea
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Wyss C, Moter A, Choi BK, Dewhirst FE, Xue Y, Schüpbach P, Göbel UB, Paster BJ, Guggenheim B. Treponema putidum sp. nov., a medium-sized proteolytic spirochaete isolated from lesions of human periodontitis and acute necrotizing ulcerative gingivitis. Int J Syst Evol Microbiol 2004; 54:1117-1122. [PMID: 15280279 DOI: 10.1099/ijs.0.02806-0] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
So far, little phenotypic heterogeneity has been detected in cultured oral treponemes with trypsin-like proteolytic activity, and all have been assigned to the species Treponema denticola. However, comparisons of protein patterns and antigen expression in our collection of proteolytic oral treponemes occasionally identified isolates with a unique phenotype; e.g. strain OMZ 830 (=ATCC 700768), which qualified as a ‘pathogen-related oral spirochaete’ due to the presence of a ∼37 kDa protein reactive with the Treponema pallidum FlaA-specific mAb H9-2. In addition to such single isolates, a homogeneous group of seven independent strains is described that were highly motile, medium-sized, proteolytic but asaccharolytic spirochaetes and were cultured from human gingivitis, periodontitis and acute necrotizing ulcerative gingivitis in medium OMIZ-Pat supplemented with 1 % human serum and antibiotics. Growth of these spirochaetes in OMIZ-Pat was not dependent on, but was stimulated by, human or bovine serum. Carbohydrates were neither required nor stimulatory for growth. The protein and antigen patterns of total cell extracts of these organisms separated by SDS-PAGE were distinct from those of all previously cultured spirochaetes, with highest similarity to T. denticola. The novel spirochaete has a 2 : 4 : 2 arrangement of the periplasmic flagella, similar to T. denticola. However, the flagellin pattern as detected by immunostaining or glycan staining of Western blots readily distinguished the novel group from T. denticola. Also, distinct from reference strains of T. denticola, none of the novel isolates displayed sialidase or dentilisin activities, both of which are expressed by most strains of T. denticola. Trypsin-like activity and other enzymes as detected by API ZYM test were similar to those of T. denticola. The status of a novel species is supported by the 16S rRNA gene sequence, with 98·5 % similarity to its closest cultured relative, T. denticola. The name Treponema putidum sp. nov. is proposed (type strain OMZ 758T=ATCC 700334T=CIP 108088T).
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MESH Headings
- Antigens, Bacterial/analysis
- Antigens, Bacterial/immunology
- Bacterial Proteins/analysis
- Bacterial Proteins/immunology
- Carbohydrate Metabolism
- Chymotrypsin/metabolism
- Culture Media/chemistry
- DNA, Bacterial/chemistry
- DNA, Bacterial/isolation & purification
- DNA, Ribosomal/chemistry
- Flagella/chemistry
- Flagella/immunology
- Flagellin/analysis
- Flagellin/immunology
- Genes, rRNA
- Gingivitis, Necrotizing Ulcerative/microbiology
- Humans
- Molecular Sequence Data
- Movement
- Neuraminidase/metabolism
- Peptide Hydrolases/metabolism
- Periodontitis/microbiology
- Phylogeny
- Proteins/metabolism
- Proteome
- RNA, Bacterial/genetics
- RNA, Ribosomal, 16S/genetics
- Sequence Analysis, DNA
- Sequence Homology
- Sucrose/metabolism
- Treponema/classification
- Treponema/cytology
- Treponema/isolation & purification
- Treponema/physiology
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Affiliation(s)
- C Wyss
- Institut für Orale Mikrobiologie und Allgemeine Immunologie, Zentrum für Zahn-, Mund- und Kieferheilkunde der Universität Zürich, Plattenstrasse 11, CH-8028 Zürich, Switzerland
| | - A Moter
- Charité-Universitätsmedizin Berlin, Institut für Mikrobiologie und Hygiene, Dorotheenstrasse 96, D-10117 Berlin, Germany
| | - B-K Choi
- Department of Oromaxillofacial Infection and Immunity, College of Dentistry, Seoul National University, 110-749 Seoul, Korea
| | - F E Dewhirst
- Department of Molecular Genetics, The Forsyth Institute, 140 Fenway, Boston, MA 02115, USA
| | - Yi Xue
- Institut für Orale Mikrobiologie und Allgemeine Immunologie, Zentrum für Zahn-, Mund- und Kieferheilkunde der Universität Zürich, Plattenstrasse 11, CH-8028 Zürich, Switzerland
| | - P Schüpbach
- Institut für Orale Mikrobiologie und Allgemeine Immunologie, Zentrum für Zahn-, Mund- und Kieferheilkunde der Universität Zürich, Plattenstrasse 11, CH-8028 Zürich, Switzerland
| | - U B Göbel
- Charité-Universitätsmedizin Berlin, Institut für Mikrobiologie und Hygiene, Dorotheenstrasse 96, D-10117 Berlin, Germany
| | - B J Paster
- Department of Molecular Genetics, The Forsyth Institute, 140 Fenway, Boston, MA 02115, USA
| | - B Guggenheim
- Institut für Orale Mikrobiologie und Allgemeine Immunologie, Zentrum für Zahn-, Mund- und Kieferheilkunde der Universität Zürich, Plattenstrasse 11, CH-8028 Zürich, Switzerland
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Ehmke B, Beikler T, Riep B, Flemmig T, Göbel U, Moter A. Intraoral dissemination of treponemes after periodontal therapy. Clin Oral Investig 2004; 8:219-25. [PMID: 15221659 DOI: 10.1007/s00784-004-0272-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2004] [Accepted: 05/11/2004] [Indexed: 10/26/2022]
Abstract
Oral treponemes are related to chronic periodontitis, but the effect of periodontal therapy on the majority of treponemal species is unknown. The aim of this prospective study was to evaluate the dynamics in prevalence profiles of treponemes in different habitats of the oral cavity. Thirty-five patients with chronic periodontitis were randomly assigned to mechanical debridement alone (control group) or systemic amoxicillin/metronidazole plus chlorhexidine (test group). Subgingival and mucous membrane plaque samples were taken at baseline, after 10 days, and during supportive periodontal therapy at 3, 6, 9, 12, 18, and 24 months. T. denticola, T. lecithinolyticum, T. maltophilum, T. socranskii, T. vincentii, and treponemal phylotypes I-VII were detected using polymerase chain reaction (PCR) and dot blot analysis. For the majority of the assessed treponemes, a significant intragroup increase in prevalence in the different habitats ( P<0.05) occurred over the study course but, compared to debridement alone, adjunctive antimicrobial therapy resulted in a nonsignificant trend toward lower prevalence in the subgingival habitat. In no case were treponemes eradicated from the oral cavity. After both therapies, possibly new infection with and/or dissemination of Treponema ssp. occurred, which led to treponemes recovering in different habitats and to increased intraoral prevalence. The prescribed adjunctive antimicrobial therapy may limit this increase in the subgingival region.
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Affiliation(s)
- Benjamin Ehmke
- Department of Periodontology, Westfalian Wilhelm University, Waldeyerstrasse 30, 48149 Münster, Germany.
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Abstract
There have been major recent reorganizations among bacterial taxa as a result of phylogenetic taxonomic approaches. As a consequence, old species have been renamed and novel species have been proposed. The introduction of molecular technology for microbial identification has also allowed the detection of microbial taxa never previously found in endodontic infections. Therefore, the list of putative endodontic pathogens is frequently changing and expanding. The purpose of this review is twofold: to cover the taxonomic changes that the major putative endodontic pathogens have undergone in the recent years and to compile data from studies regarding the detection of known or novel bacterial species that had been only recently reported to occur in endodontic infections.
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Affiliation(s)
- José F Siqueira
- Department of Endodontics, Faculty of Dentistry, Estácio de Sá University, Rio de Janeiro, Brazil.
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Siqueira JF, Rôças IN. PCR-based identification of Treponema maltophilum, T amylovorum, T medium, and T lecithinolyticum in primary root canal infections. Arch Oral Biol 2003; 48:495-502. [PMID: 12798152 DOI: 10.1016/s0003-9969(03)00092-x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
OBJECTIVE Molecular genetic methods have significantly contributed to the knowledge about the microbiota associated with infected root canals. Albeit spirochetes have been commonly observed in primary root canal infections, only recently they have been identified. The purpose of the present study was to investigate the occurrence of four treponemes-Treponema maltophilum, Treponema lecithinolyticum, Treponema amylovorum, and Treponema medium-in cases of primary endodontic infections associated with different forms of periradicular diseases through a 16S rDNA-based nested PCR assay. DESIGN Samples were taken from thirty-one infected root canals associated with either asymptomatic or symptomatic apical periodontitis. DNA extracted from the samples was initially amplified using universal 16S rDNA primers, followed by a second round of amplification using the first PCR products to detect a specific fragment of the 16S rDNA of each target Treponema species. RESULTS All cases were positive for the universal bacterial primers, indicating that samples contained bacterial DNA. Of the four target species, T. maltophilum was the most prevalent, being detected in 39% of the cases (33% of the asymptomatic cases and 50% of the symptomatic cases). T. lecithinolyticum was the next more prevalent among the species tested, being found in 26% of the samples (33% of asymptomatic cases and 10% of the symptomatic cases). T. amylovorum was found in 7% of the cases (5% of the asymptomatic cases and 10% of the symptomatic cases), while T. medium was in 13% of the cases (14% of the asymptomatic cases and 10% of the symptomatic cases). None of the species tested was significantly associated with clinical symptoms. CONCLUSIONS This was possibly the hitherto first study to report the occurrence of T. lecithinolyticum, T. amylovorum, and T. medium in infections of endodontic origin. Overall, findings suggested that these oral treponemes, particularly T. maltophilum and T. lecithinolyticum, can be involved in the pathogenesis of periradicular diseases.
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Affiliation(s)
- José F Siqueira
- Department of Endodontics, Faculty of Dentistry, Estácio de Sá University, Rio de Janeiro, RJ 20261, Brazil.
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Nakazawa F, Hoshino E, Fukunaga M, Jinno T, Asai Y, Yamamoto H, Ogawa T. Amended biochemical characteristics and phylogenetic position of Treponema medium. ORAL MICROBIOLOGY AND IMMUNOLOGY 2003; 18:127-30. [PMID: 12654104 DOI: 10.1034/j.1399-302x.2003.00015.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Umemoto et al. (1997, Int J Syst Bacteriol 47, pp. 67-72) proposed spirochete strain G7201, isolated from the periodontal pocket of an adult patient, as a new species, Treponema medium. They deposited this strain in the American Type Culture Collection (ATCC) as type strain ATCC 700293T. Recently, ATCC suggested that there is a discrepancy between the previous report and the results obtained by ATCC in biochemical tests on T. medium ATCC 700293T. In this study, we re-examined and verified the biochemical characteristics of T. medium. The fermentation pattern of carbohydrates of T. medium resembled that of Treponema vincentii and Treponema denticola, but T. medium was clearly differentiated from T. vincentii in the production of indole, and from T. denticola in the hydrolysis of esculin. Also, sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE) protein profile analysis and phylogenetic comparison of 16S rDNA sequences revealed that T. medium is clearly differentiated from any established treponemal species, which supports the validity of the proposal of Treponema medium as a new species.
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Affiliation(s)
- F Nakazawa
- Department of Oral Health Science, Niigata University Graduate School of Medical and Dental Science, Niigata, Japan
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Choi BK, Lee HJ, Kang JH, Jeong GJ, Min CK, Yoo YJ. Induction of osteoclastogenesis and matrix metalloproteinase expression by the lipooligosaccharide of Treponema denticola. Infect Immun 2003; 71:226-33. [PMID: 12496170 PMCID: PMC143274 DOI: 10.1128/iai.71.1.226-233.2003] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Alveolar bone destruction is a characteristic feature of periodontitis. Treponema denticola is known to be involved in periodontitis. To elucidate the role of T. denticola in alveolar bone destruction in periodontitis, the effects of lipooligosaccharide (LOS) from T. denticola on osteoclast formation and on expression of osteoclast differentiation factor (ODF) and osteoprotegerin (OPG) mRNAs were examined in a coculture system by using mouse calvaria and bone marrow cells. In addition, the effect of T. denticola LOS on expression of matrix metalloproteinases (MMPs), which are involved in bone resorption, was estimated in mouse calvaria-derived osteoblastic cells. When the mouse calvaria and bone marrow cells were challenged with LOS (0.1 to 10 micro g/ml) for 4 days, the number of tartrate-resistant acid phosphatase-positive multinucleated cells increased in a dose-dependent manner. The expression of ODF mRNA increased, while OPG mRNA expression decreased. Polymyxin B changed the effect of LOS (10 micro g/ml) on ODF and OPG mRNA expression to the control level. LOS (10 micro g/ml) stimulated prostaglandin E(2) (PGE(2)) production in the cocultures. Adding indomethacin, an inhibitor of prostaglandin synthesis, resulted in a reduction in the number of osteoclasts induced by LOS and eliminated the effect of T. denticola LOS on ODF and OPG mRNA expression. T. denticola LOS increased the levels of mRNAs encoding MMP-3, -8, -9, -10, -13, and -14. Expression of one of these mRNAs, MMP-9 mRNA, was significantly induced by T. denticola LOS. These findings suggest that LOS from T. denticola stimulates osteoclastogenesis and MMP expression. Up-regulation of ODF and down-regulation of OPG by a PGE(2)-dependent mechanism were involved in the osteoclastogenesis induced by T. denticola LOS.
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Affiliation(s)
- Bong-Kyu Choi
- Department of Oral Biology, College of Dentistry, Brain Korea 21 Project for Medical Sciences, Yonsei University, Seoul, Korea
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Rôças IN, Siqueira JF, Andrade AFB, Uzeda M. Oral treponemes in primary root canal infections as detected by nested PCR. Int Endod J 2003; 36:20-6. [PMID: 12656510 DOI: 10.1046/j.0143-2885.2003.00607.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
AIM To investigate the prevalences of four Treponema species in primary root canal infections using a nested PCR assay. METHODOLOGY Samples were obtained from 32 infected root canals. Twenty-two cases showed chronic asymptomatic periradicular lesions and 10 symptomatic cases were diagnosed as acute apical periodontitis. DNA extracted from the samples was initially amplified using universal 16S rDNA primers. A second round of amplification used the first PCR products to detect a specific fragment of the 16S rDNA of each Treponema denticola, T. socranskii, T. vincentii and T. pectinovorum. RESULTS Bacteria were present in all cases sampled. T. denticola was detected in 77.3% of the asymptomatic cases, T. socranskii in 40.9%, T. vincentii in 18.2% and T. pectinovorum in 13.6%. In the cases diagnosed as acute apical periodontitis, T. denticola was detected in 80%, whilst T. socranskii and T. vincentii were detected in 40% and 10% of cases, respectively. No symptomatic case yielded T. pectinovorum. In general, nested PCR detected T. denticola in 78.1% of the cases, T. socranskii in 40.6%, T. vincentii in 15.6% and T. pectinovorum in 9.4%. At least one of the four Treponema species was found in 84.4% of the cases examined. CONCLUSIONS The species T. denticola was detected in a large number of the cases examined: the prevalence of T. socranskii was also relatively high. The species T. vincentii and T. pectinovorum were also found, but in a smaller number of cases. Based on these data, the recognized pathogenicity of these microorganisms and their involvement with other oral diseases, they should be included in the restricted set of putative endodontic pathogens.
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Affiliation(s)
- I N Rôças
- Department of Endodontics, Faculty of Dentistry, Estácio de Sá University, State University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
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Abstract
The motility and chemotaxis of human oral spirochetes Treponema denticola ATCC 35404, T. medium ATCC 700293, and T. vincentii ATCC 35580 were examined by a capillary assay method. Of five sera three human oral treponemes were dominantly chemoattractant to the rabbit serum. The checkerboard analysis of chemotaxis toward rabbit serum clearly showed that the motile T. denticola cells swam toward the culture media containing higher concentrations of the rabbit serum. T. denticola chemotaxis to the rabbit serum was clearly reduced by heating serum, and rabbit albumin contributed by 60 to 70% to its chemotaxis to the rabbit serum. Western blotting analysis demonstrated that these treponemes possessed rabbit albumin-binding polypeptides with approximate molecular sizes of 65 kDa and 70 kDa. Immunoelectron microscopy demonstrated that a 65 kDa rabbit albumin-binding polypeptide was located on the outer envelopes, suggesting that the rabbit albumin-binding polypeptide is responsible for chemotaxis toward rabbit serum.
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Affiliation(s)
- T Umemoto
- Department of Oral Microbiology, Asahi University School of Dentistry, Gifu, Japan.
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Stamm LV, Bergen HL, Shangraw KA. Natural rifampin resistance in Treponema spp. correlates with presence of N531 in RpoB rif cluster i. Antimicrob Agents Chemother 2001; 45:2973-4. [PMID: 11702716 PMCID: PMC90769 DOI: 10.1128/aac.45.10.2973-2974.2001] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Choi BK, Ohk SH, Lee HJ, Kang JH, Jeong GJ, Yoo YJ. Effects of whole cell sonicates of Treponema lecithinolyticum on osteoclast differentiation. J Periodontol 2001; 72:1172-7. [PMID: 11577948 DOI: 10.1902/jop.2000.72.9.1172] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND Alveolar bone destruction is a characteristic feature of periodontal diseases and multinucleated osteoclast cells derived from hemopoietic cells are responsible for bone resorption. Treponema lecithinolyticum is a novel oral spirochete isolated from the periodontal lesions. METHODS The effect of whole cell sonicates on the osteoclast differentiation was examined in a co-culture system of hemopoietic mouse bone marrow cells and calvaria derived-osteoblastic cells to clarify the role of T. lecithinolyticum in the alveolar bone destruction associated with periodontal diseases. The differentiated osteoclasts were confirmed by tartrate-resistant acid phosphatase (TRAP) staining. RESULTS Sonicates of this bacterium stimulated the osteoclast formation in the co-culture system in a dose-dependent manner. The sonicates-induced osteoclast formation was partially inhibited by the heat treatment of sonicates. Indomethacin, which is a prostaglandin inhibitor, decreased the osteoclast formation induced by the bacterial sonicates. CONCLUSIONS These findings suggest that T. lecithinolyticum induces osteoclast differentiation by a prostaglandin E2-dependent mechanism and that heat-labile components may be involved in this process.
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Affiliation(s)
- B K Choi
- Department of Oral Biology, College of Dentistry, and Brain Korea 21 Project for Medical Sciences, Yonsei University, Seoul, Korea
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Jung IY, Choi B, Kum KY, Yoo YJ, Yoon TC, Lee SJ, Lee CY. Identification of oral spirochetes at the species level and their association with other bacteria in endodontic infections. ORAL SURGERY, ORAL MEDICINE, ORAL PATHOLOGY, ORAL RADIOLOGY, AND ENDODONTICS 2001; 92:329-34. [PMID: 11552154 DOI: 10.1067/moe.2001.117263] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVES Recent molecular approaches have revealed that fastidious organisms such as Bacteroides forsythus and oral treponemes were frequently found in root canals with apical periodontitis. The purpose of this study was to identify the isolates of oral spirochetes at the species level in endodontic infections and to determine their association with B forsythus and Porphyromonas gingivalis. STUDY DESIGN Seventy-nine teeth with apical periodontitis were selected for this study. After sampling from the root canals aseptically, polymerase chain reaction amplification for the 16S rRNA gene was performed with eubacterial universal primers. Subsequently, dot-blot hybridization was performed with 8 species-specific oligonucleotide probes. The microbial associations were analyzed by using the odds ratio. RESULTS The most frequently found species was P gingivalis (27.4%), followed by Treponema maltophilum (26%), B forsythus (16.4%), and Treponema socranskii (2.7%). Other treponemes, including Treponema denticola, were not detected in our samples. Significant microbial associations were identified between T maltophilum, B forsythus, and P gingivalis by performing analysis with the odds ratio. CONCLUSION Our results indicate that T maltophilum should be included in etiologic studies of endodontic diseases.
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Affiliation(s)
- I Y Jung
- Department of Conservative Dentistry and Oral Science Research Center, Yonsei University, Seoul, Korea
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Opitz B, Schröder NW, Spreitzer I, Michelsen KS, Kirschning CJ, Hallatschek W, Zähringer U, Hartung T, Göbel UB, Schumann RR. Toll-like receptor-2 mediates Treponema glycolipid and lipoteichoic acid-induced NF-kappaB translocation. J Biol Chem 2001; 276:22041-7. [PMID: 11285258 DOI: 10.1074/jbc.m010481200] [Citation(s) in RCA: 173] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Recently Toll-like receptors (TLRs) have been found to be involved in cellular activation by microbial products, including lipopolysaccharide, lipoproteins, and peptidoglycan. Although for these ligands the specific transmembrane signal transducers TLR-4, TLR-2, or TLR-2 and -6 have now been identified, the molecular basis of recognition of lipoteichoic acids (LTAs) and related glycolipids has not been completely understood. In order to determine the role of TLRs in immune cell activation by these stimuli, experiments involving TLR-2-negative cell lines, TLR-expression plasmids, macrophages from TLR-4-deficient C3H/HeJ-mice, and inhibitory TLR-4/MD-2 antibodies were performed. Glycolipids from Treponema maltophilum and Treponema brennaborense, as well as highly purified LTAs from Staphylococcus aureus and Bacillus subtilis exhibited TLR-2 dependence in nuclear factor kappaB activation and cytokine induction; however, T. brennaborense additionally appeared to signal via TLR-4. Fractionation of the T. brennaborense glycolipids by hydrophobic interaction chromatography and subsequent cell stimulation experiments revealed two peaks of activity, one exhibiting TLR-2-, and a second TLR-4-dependence. Furthermore, we show involvement of the signaling molecules MyD88 and NIK in cell stimulation by LTAs and glycolipids by dominant negative overexpression experiments. In summary, the results presented here indicate that TLR-2 is the main receptor for Treponema glycolipid and LTA-mediated inflammatory response.
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Affiliation(s)
- B Opitz
- Institut für Mikrobiologie und Hygiene, Charité Medical Center, Humboldt-University, 10117 Berlin, Germany
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Heuner K, Meltzer U, Choi BK, Göbel UB. Outer sheath associated proteins of the oral spirochete Treponema maltophilum. FEMS Microbiol Lett 2001; 197:187-93. [PMID: 11313133 DOI: 10.1111/j.1574-6968.2001.tb10602.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
We recently cloned the major outer membrane protein of Treponema maltophilum [Heuner, K., Choi, B.K., Schade, R., Moter, A., Otto, A., Göbel, U.B., J. Bacteriol. 181, 1025-1029]. Here we report the localization of the major sheath protein (Msp)A protein in T. maltophilum by immunogold electron microscopy and its expression. Northern blot analysis revealed that mspA is expressed constitutively as a monocistronic unit. The transcription initiation site of the mspA gene was identified by primer extension analysis. A further screening of a genomic library of T. maltophilum with an anti-outer membrane fraction antibody was done. We were able to clone DNA regions of T. maltophilum encoding putative sugar transport operons and putative outer membrane proteins of this oral treponeme which has a high prevalence in periodontal lesions.
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Affiliation(s)
- K Heuner
- Institut für Mikrobiologie und Hygiene, Universitätsklinikum Charité, Humboldt-Universität zu Berlin, Germany.
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Schröder NW, Pfeil D, Opitz B, Michelsen KS, Amberger J, Zähringer U, Göbel UB, Schumann RR. Activation of mitogen-activated protein kinases p42/44, p38, and stress-activated protein kinases in myelo-monocytic cells by Treponema lipoteichoic acid. J Biol Chem 2001; 276:9713-9. [PMID: 11134043 DOI: 10.1074/jbc.m008954200] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We have shown previously that phenol/water extracts derived from two novel Treponema species, Treponema maltophilum, and Treponema brennaborense, resembling lipoteichoic acid (LTA), induce cytokines in mononuclear cells. This response was lipopolysaccharide binding-protein (LBP)-dependent and involved Toll-like receptors (TLRs). Here we show that secretion of tumor necrosis factor-alpha induced by Treponema culture supernatants and extracted LTA was paralleled by an LBP-dependent phosphorylation of mitogen-activated protein kinases (MAPKs) p42 and p44, and p38, as well as the stress-activated protein kinases c-Jun N-terminal kinases 1 and 2. Phosphorylation of p42/44 correlated with an increase of activity, and tumor necrosis factor-alpha levels were significantly reduced by addition of inhibitors of p42/44 and p38, PD 98059 and SB 203580, respectively. Treponeme LTA differed from bacterial lipopolysaccharide regarding time course of p42/44 phosphorylation, exhibiting a prolonged activation of MAPKs. Furthermore, MAPK activation and cytokine induction failed to be strictly correlated. Involvement of TLR-4 for phosphorylation of p42/44 was shown employing the neutralizing anti-murine TLR-4 antibody MTS 510. In TLR-2-negative U373 cells, the compounds studied differed regarding MAPK activation with T. maltophilum leading to a stronger activation. In summary, the data presented here show that treponeme LTA are able to activate the MAPK and stress-activated protein kinase pathway involving LBP and TLR-4.
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Affiliation(s)
- N W Schröder
- Institut für Mikrobiologie und Hygiene, Universitätsklinikum "Charité," Medizinische Fakultät der Humboldt-Universität zu Berlin, Dorotheenstrasse 96, D-10117 Berlin, Germany
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Schröder NW, Opitz B, Lamping N, Michelsen KS, Zähringer U, Göbel UB, Schumann RR. Involvement of lipopolysaccharide binding protein, CD14, and Toll-like receptors in the initiation of innate immune responses by Treponema glycolipids. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2000; 165:2683-93. [PMID: 10946299 DOI: 10.4049/jimmunol.165.5.2683] [Citation(s) in RCA: 107] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Culture supernatants from Treponema maltophilum associated with periodontitis in humans and Treponema brennaborense found in a bovine cattle disease accompanied with cachexia caused a dose-dependent TNF-alpha synthesis in human monocytes increasing with culture time. This activity could be reduced significantly by blocking the CD14-part of the LPS receptor using the My 4 mAb and by polymyxin B. In the murine macrophage cell line RAW 264.7, Treponema culture supernatants induced TNF-alpha secretion in a LPS binding protein (LBP)-dependent fashion. To enrich for active compounds, supernatants were extracted with butanol, while whole cells were extracted using a phenol/water method resulting in recovery of material exhibiting a similar activity profile. An LPS-LBP binding competition assay revealed an interaction of the treponeme phenol/water extracts with LBP, while precipitation studies implied an affinity to polymyxin B and endotoxin neutralizing protein. Macrophages obtained from C3H/HeJ mice carrying a Toll-like receptor (TLR)-4 mutation were stimulated with treponeme extracts for NO release to assess the role of TLRs in cell activation. Furthermore, NF-kappaB translocation in TLR-2-negative Chinese hamster ovary (CHO) cells was studied. We found that phenol/water-extracts of the two strains use TLRs differently with T. brennaborense-stimulating cells in a TLR-4-dependent fashion, while T. maltophilum-mediated activation apparently involved TLR-2. These results indicate the presence of a novel class of glycolipids in Treponema initiating inflammatory responses involving LBP, CD14, and TLRs.
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Affiliation(s)
- N W Schröder
- Institut für Mikrobiologie und Hygiene, Universitätsklinikum Charité Medizinische Fakultät der Humboldt-Universität zu Berlin, Berlin, Germany
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Dewhirst FE, Tamer MA, Ericson RE, Lau CN, Levanos VA, Boches SK, Galvin JL, Paster BJ. The diversity of periodontal spirochetes by 16S rRNA analysis. ORAL MICROBIOLOGY AND IMMUNOLOGY 2000; 15:196-202. [PMID: 11154403 DOI: 10.1034/j.1399-302x.2000.150308.x] [Citation(s) in RCA: 140] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The purpose of this study was to examine the diversity of spirochetes in the subgingival pocket of multiple subjects with a range of periodontal conditions, including two healthy, one adult periodontitis, three acute necrotizing ulcerative gingivitis, eight refractory periodontitis, and one human immunodeficiency virus (HIV) periodontitis. The 16S rRNA genes of spirochetes in plaque were amplified by polymerase chain reaction using spirochete selective primers. Over 500 clones were sequenced and subjected to phylogenetic analysis. The sequences clustered into the 10 known cultivated Treponema species and into 47 as-yet-uncultivated Treponema species. Most of these Treponema species were identified from multiple clones and subjects. The human periodontal pocket harbors a highly diverse treponeme population. Of the cultivated species, Treponema denticola, Treponema maltophilum and Treponema sp. Smibert-3 were most commonly encountered in diseased subjects but rarely in healthy subjects. Molecular tools based on the sequence data from this study will allow determination of the prevalence of cultivable and uncultivable treponemes in oral diseases.
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Affiliation(s)
- F E Dewhirst
- Department of Molecular Genetics, Forsyth Institute, 140 The Fenway, Boston, MA 02115, USA
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Dubreuil L, Behra-Miellet J. Bactéries anaérobies strictes: Taxonomie et bilan de sensibilité aux antimicrobiens. Med Mal Infect 2000. [DOI: 10.1016/s0399-077x(00)89106-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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