Genetic Basis of Coaggregation Receptor Polysaccharide Biosynthesis in Streptococcus sanguinis and Related Species
This article is protected by copyright. All rights reserved. (Source: Oral Microbiology and Immunology)
Source: Oral Microbiology and Immunology - November 12, 2013 Category: Microbiology Authors: Jinghua Yang, Yasuo Yoshida, John O. Cisar Tags: Original Article Source Type: research
Localization and function of the accessory protein Mfa3 in Porphyromonas gingivalis Mfa1 fimbriae
Summary
The fimbriae of Porphyromonas gingivalis, the causative agent of periodontitis, have been implicated in various aspects of pathogenicity, such as colonization, adhesion and aggregation. Porphyromonas gingivalis ATCC 33277 has two adhesins comprised of the FimA and Mfa1 fimbriae. We characterized the PGN0289 (Mfa3) protein, which is one of the three accessory proteins of Mfa1 fimbriae in P. gingivalis. The Mfa3 protein was present in two different sizes, 40 and 43 kDa, in the cell. The 43‐kDa and 40‐kDa Mfa3 were detected largely in the inner membrane and the outer membrane, respectively. Purified Mfa1 fimbria...
Source: Oral Microbiology and Immunology - October 4, 2013 Category: Microbiology Authors: Y. Hasegawa, K. Nagano, R. Ikai, M. Izumigawa, Y. Yoshida, N. Kitai, R.J. Lamont, Y. Murakami, F. Yoshimura Tags: Original Article Source Type: research
Cnm is a major virulence factor of invasive Streptococcus mutans and part of a conserved three‐gene locus
This article is protected by copyright. All rights reserved. (Source: Oral Microbiology and Immunology)
Source: Oral Microbiology and Immunology - September 23, 2013 Category: Microbiology Authors: Alejandro Avilés‐Reyes, James H. Miller, Patricia J. Simpson‐Haidaris, José A. Lemos, Jacqueline Abranches Tags: Original Article Source Type: research
Localization and function of the accessory protein Mfa3 in Porphyromonas gingivalis Mfa1 fimbriae
This article is protected by copyright. All rights reserved. (Source: Oral Microbiology and Immunology)
Source: Oral Microbiology and Immunology - September 5, 2013 Category: Microbiology Authors: Y. Hasegawa, K. Nagano, R. Ikai, M. Izumigawa, Y. Yoshida, N. Kitai, R. J. Lamont, Y. Murakami, F. Yoshimura Tags: Original Article Source Type: research
A role for the DtxR family of metalloregulators in gram‐positive pathogenesis
Summary
Given the central role of transition metal ions in a variety of biochemical processes, the colonization, survival, and proliferation of a bacterium within a host hinges upon its ability to overcome the metal ion deprivation that characterizes nutritional immunity. Metalloregulatory, or ‘metal‐sensing’ proteins have evolved in bacteria to mediate metal ion homeostasis by activating or repressing the expression of genes encoding metal ion transport systems upon binding their cognate metal ion. Yet increasing evidence in the literature supports an additional role for these metalloregulatory proteins in pathogene...
Source: Oral Microbiology and Immunology - August 22, 2013 Category: Microbiology Authors: A.T. Merchant, G.A. Spatafora Tags: Invited Review Source Type: research
Identification of gingipain‐specific I‐Ab‐restricted CD4+ T cells following mucosal colonization with Porphyromonas gingivalis in C57BL/6 mice
Summary
Chronic periodontitis is associated with Porphyromonas gingivalis infection. Although virulence factors of P. gingivalis are hypothesized to contribute to the pathogenesis of periodontitis, it is unclear whether the local CD4+ T‐cell‐mediated response they elicit prevents or contributes to periodontal bone destruction. We hypothesize that major histocompatibility complex class II I‐Ab‐binding peptides existing in Kgp and RgpA are presented to CD4+ T cells during P. gingivalis oral colonization. The protein sequences of gingipains RgpA and Kgp, and OMP40 and OMP41 of P. gingivalis were scanned using an I...
Source: Oral Microbiology and Immunology - August 14, 2013 Category: Microbiology Authors: P.D. Bittner‐Eddy, L.A. Fischer, M. Costalonga Tags: Original Article Source Type: research
Periodontal innate immune mechanisms relevant to obesity
Summary
Obesity affects over 35% of the adult population of the USA, and obesity‐related illnesses have emerged as the leading cause of preventable death worldwide, according to the World Health Organization. Obesity's secondary morbidities include increased risk of cardiovascular disease, type II diabetes, and cancer, in addition to increased occurrence and severity of infections. Sedentary lifestyle and weight gain caused by consumption of a high‐fat diet contribute to the development of obesity, with individuals having a body mass index (BMI) score > 30 being considered obese. Genetic models of obesity (ob/ob mi...
Source: Oral Microbiology and Immunology - August 5, 2013 Category: Microbiology Authors: S. Amar, S. Leeman Tags: Review Source Type: research
MyD88 is essential for alveolar bone loss induced by Aggregatibacter actinomycetemcomitans lipopolysaccharide in mice
Summary
Aggregatibacter actinomycetemcomitans is a Gram‐negative bacteria highly associated with localized aggressive periodontitis. The recognition of microbial factors, such as lipopolysaccharide from A. actinomycetemcomitans (AaLPS), in the oral environment is made mainly by surface receptors known as Toll‐like receptors (TLR). TLR4 is the major LPS receptor. This interaction leads to the production of inflammatory cytokines by myeloid differentiation primary‐response protein 88 (MyD88) ‐dependent and ‐independent pathways, which may involve the adaptor Toll/interleukin‐1 receptor‐domain‐containing adap...
Source: Oral Microbiology and Immunology - July 30, 2013 Category: Microbiology Authors: M.F.M. Madeira, C.M. Queiroz‐Junior, D. Cisalpino, S.M.C. Werneck, H. Kikuchi, O. Fujise, B. Ryffel, T.A. Silva, M.M. Teixeira, D.G. Souza Tags: Original Article Source Type: research
Oral Fusobacterium nucleatum subsp. polymorphum binds to human salivary α‐amylase
In this study, we showed that F. nucleatum subsp. polymorphum can bind to a salivary component with a molecular weight of approximately 110 kDa and identified the protein and another major factor of 55 kDa, as salivary α‐amylase by time‐of‐flight mass spectrometry and immuno‐reactions. Salivary α‐amylase is present in both monomeric and dimeric forms and we found that formation of the dimer depends on copper ions. The F. nucleatum adhered to both monomeric and dimeric salivary α‐amylases, but the numbers of bacteria bound to the dimeric form were more than those bound to the monomeric form. The degree of...
Source: Oral Microbiology and Immunology - July 30, 2013 Category: Microbiology Authors: M. Zulfiqar, T. Yamaguchi, S. Sato, T. Oho Tags: Original Article Source Type: research
Erythritol alters microstructure and metabolomic profiles of biofilm composed of Streptococcus gordonii and Porphyromonas gingivalis
Summary
The effects of sugar alcohols such as erythritol, xylitol, and sorbitol on periodontopathic biofilm are poorly understood, though they have often been reported to be non‐cariogenic sweeteners. In the present study, we evaluated the efficacy of sugar alcohols for inhibiting periodontopathic biofilm formation using a heterotypic biofilm model composed of an oral inhabitant Streptococcus gordonii and a periodontal pathogen Porphyromonas gingivalis. Confocal microscopic observations showed that the most effective reagent to reduce P. gingivalis accumulation onto an S. gordonii substratum was erythritol, as compared...
Source: Oral Microbiology and Immunology - July 29, 2013 Category: Microbiology Authors: E. Hashino, M. Kuboniwa, S.A. Alghamdi, M. Yamaguchi, R. Yamamoto, H. Cho, A. Amano Tags: Original Article Source Type: research
A role for the DtxR family of metalloregulators in gram‐positive pathogenesis
This article is protected by copyright. All rights reserved. (Source: Oral Microbiology and Immunology)
Source: Oral Microbiology and Immunology - July 19, 2013 Category: Microbiology Authors: Anjali T. Merchant, Grace. A Spatafora Tags: Invited Review Source Type: research
Identification of gingipain‐specific I‐Ab‐restricted CD4+ T cells following mucosal colonization with Porphyromonas gingivalis in C57BL/6 mice
This article is protected by copyright. All rights reserved. (Source: Oral Microbiology and Immunology)
Source: Oral Microbiology and Immunology - July 15, 2013 Category: Microbiology Authors: Peter D. Bittner‐Eddy, Lori Ann Fischer, Massimo Costalonga Tags: Original Article Source Type: research
Perturbation of the indigenous rat oral microbiome by ciprofloxacin dosing
The objective of this study was to characterize the rat oral plaque microbiome composition at doses of ciprofloxacin that were considerably above and below nominal in vitro minimal inhibitory concentrations of a variety of gram‐positive oral commensal bacteria. We exposed the oral cavities of rats to relatively low (0.1 μg ml−1) and high (20 μg ml−1) doses of ciprofloxacin in the drinking water over a 3‐day period. Plaque microbiota were characterized using 454 pyrosequencing. The rat indigenous community was dominated by the genera Rothia (74.4%) and Streptococcus (4.7%). Dosing at 0.1 μg ml−1 was assoc...
Source: Oral Microbiology and Immunology - July 12, 2013 Category: Microbiology Authors: P. Manrique, M.O. Freire, C. Chen, H.H. Zadeh, M. Young, P. Suci Tags: Original Article Source Type: research
Genetic and antigenic analyses of Porphyromonas gingivalis FimA fimbriae
Summary
The periodontal pathogen Porphyromonas gingivalis generally expresses two distinct fimbriae, FimA and Mfa1, which play a role in biofilm formation. The fimA gene that encodes FimA fimbrilin is polymorphic, and polymerase chain reaction analysis has identified six genotypes called types I–V and Ib. We found recently that fimbriae exhibit antigenic heterogeneity among the genotypes. In the present study, we analysed the fimA DNA sequences of 84 strains of P. gingivalis and characterized the antigenicity of FimA fimbriae. Strains analysed here comprised 10, 16, 29, 13, 10 and 6 strains of types I, Ib, II, III, IV a...
Source: Oral Microbiology and Immunology - July 1, 2013 Category: Microbiology Authors: K. Nagano, Y. Abiko, Y. Yoshida, F. Yoshimura Tags: Original Article Source Type: research
Periodontal Innate Immune Mechanisms Relevant to Obesity
This article is protected by copyright. All rights reserved. (Source: Oral Microbiology and Immunology)
Source: Oral Microbiology and Immunology - June 22, 2013 Category: Microbiology Authors: Salomon Amar, Susan Leeman Tags: Review Article Source Type: research
