QseBC, a two‐component bacterial adrenergic receptor and global regulator of virulence in Enterobacteriaceae and Pasteurellaceae
Summary
The QseBC two‐component system (TCS) is associated with quorum sensing and functions as a global regulator of virulence. Based on sequence similarity within the sensor domain and conservation of an acidic motif essential for signal recognition, QseBC is primarily distributed in the Enterobacteriaceae and Pasteurellaceae. In Escherichia coli, QseC responds to autoinducer‐3 and/or epinephrine/norepinephrine. Binding of epinephrine/norepinephrine is inhibited by adrenergic antagonists; hence QseC functions as a bacterial adrenergic receptor. Aggregatibacter actinomycetemcomitans QseC is activated by a combinati...
Source: Oral Microbiology and Immunology - November 20, 2015 Category: Microbiology Authors: W.A. Weigel, D.R. Demuth Tags: Review Source Type: research
QseBC, a two ‐component bacterial adrenergic receptor and global regulator of virulence in Enterobacteriaceae and Pasteurellaceae
Summary
The QseBC two‐component system (TCS) is associated with quorum sensing and functions as a global regulator of virulence. Based on sequence similarity within the sensor domain and conservation of an acidic motif essential for signal recognition, QseBC is primarily distributed in the Enterobacteriaceae and Pasteurellaceae. In Escherichia coli, QseC responds to autoinducer‐3 and/or epinephrine/norepinephrine. Binding of epinephrine/norepinephrine is inhibited by adrenergic antagonists; hence QseC functions as a bacterial adrenergic receptor. Aggregatibacter actinomycetemcomitans QseC is activated by a combinati...
Source: Oral Microbiology and Immunology - November 19, 2015 Category: Microbiology Authors: W.A. Weigel, D.R. Demuth Tags: Review Source Type: research
Structure of RagB, a major immunodominant outer ‐membrane surface receptor antigen of Porphyromonas gingivalis
Summary
Porphyromonas gingivalis is the main causative agent of periodontitis. It deregulates the inflammatory and innate host immune responses through virulence factors, which include the immunodominant outer‐membrane surface receptor antigens A (PgRagA) and B (PgRagB), co‐transcribed from the rag pathogenicity island. The former is predicted to be a Ton‐dependent porin‐type translocator but the targets of this translocation and the molecular function of PgRagB are unknown. Phenomenologically, PgRagB has been linked with epithelial cell invasion and virulence according to murine models. It also acts as a Toll‐li...
Source: Oral Microbiology and Immunology - November 15, 2015 Category: Microbiology Authors: T. Goulas, I. Garcia ‐Ferrer, J.A. Hutcherson, B.A. Potempa, J. Potempa, D.A. Scott, F. Xavier Gomis‐Rüth Tags: Original Article Source Type: research
Gingipain ‐dependent augmentation by Porphyromonas gingivalis of phagocytosis of Tannerella forsythia
This study investigated the role of gingipains in the modulation by P. gingivalis of phagocytosis of Tannerella forsythia by macrophages. Phagocytosis of T. forsythia was significantly enhanced by coinfection with P. gingivalis in a multiplicity of infection‐dependent and gingipain‐dependent manner. Mutation of either Kgp or Rgp in the coinfecting P. gingivalis resulted in attenuated enhancement of T. forsythia phagocytosis. Inhibition of coaggregation between the two bacterial species reduced phagocytosis of T. forsythia in mixed infection, and this coaggregation was dependent on gingipains. Inhibition of gingip...
Source: Oral Microbiology and Immunology - November 12, 2015 Category: Microbiology Authors: Y. ‐J. Jung, H.‐K. Jun, B.‐K. Choi Tags: Original Article Source Type: research
Peroxisome proliferator‐activated receptor δ inhibits Porphyromonas gingivalis lipopolysaccharide‐induced activation of matrix metalloproteinase‐2 by downregulating NADPH oxidase 4 in human gingival fibroblasts
Summary
We investigated the roles of peroxisome proliferator‐activated receptor δ (PPARδ) in Porphyromonas gingivalis‐derived lipopolysaccharide (Pg‐LPS)‐induced activation of matrix metalloproteinase 2 (MMP‐2). In human gingival fibroblasts (HGFs), activation of PPARδ by GW501516, a specific ligand of PPARδ, inhibited Pg‐LPS‐induced activation of MMP‐2 and generation of reactive oxygen species (ROS), which was associated with reduced expression of NADPH oxidase 4 (Nox4). These effects were significantly smaller in the presence of small interfering RNA targeting PPARδ or the specific PPARδ inhibitor G...
Source: Oral Microbiology and Immunology - October 27, 2015 Category: Microbiology Authors: T. Yoo, S.A. Ham, J.S. Hwang, W.J. Lee, K.S. Paek, J.W. Oh, J.H. Kim, J.T. Do, C.W. Han, J.H. Kim, H.G. Seo Tags: Original Article Source Type: research
Peroxisome proliferator ‐activated receptor δ inhibits Porphyromonas gingivalis lipopolysaccharide‐induced activation of matrix metalloproteinase‐2 by downregulating NADPH oxidase 4 in human gingival fibroblasts
Summary
We investigated the roles of peroxisome proliferator‐activated receptor δ (PPARδ) in Porphyromonas gingivalis‐derived lipopolysaccharide (Pg‐LPS)‐induced activation of matrix metalloproteinase 2 (MMP‐2). In human gingival fibroblasts (HGFs), activation of PPARδ by GW501516, a specific ligand of PPARδ, inhibited Pg‐LPS‐induced activation of MMP‐2 and generation of reactive oxygen species (ROS), which was associated with reduced expression of NADPH oxidase 4 (Nox4). These effects were significantly smaller in the presence of small interfering RNA targeting PPARδ or the specific PPARδ inhibitor G...
Source: Oral Microbiology and Immunology - October 26, 2015 Category: Microbiology Authors: T. Yoo, S.A. Ham, J.S. Hwang, W.J. Lee, K.S. Paek, J.W. Oh, J.H. Kim, J.T. Do, C.W. Han, J.H. Kim, H.G. Seo Tags: Original Article Source Type: research
Comparison of inherently essential genes of Porphyromonas gingivalis identified in two transposon‐sequencing libraries
Summary
Porphyromonas gingivalis is a Gram‐negative anaerobe and keystone periodontal pathogen. A mariner transposon insertion mutant library has recently been used to define 463 genes as putatively essential for the in vitro growth of P. gingivalis ATCC 33277 in planktonic culture (Library 1). We have independently generated a transposon insertion mutant library (Library 2) for the same P. gingivalis strain and herein compare genes that are putatively essential for in vitro growth in complex media, as defined by both libraries. In all, 281 genes (61%) identified by Library 1 were common to Library 2. Many of these ...
Source: Oral Microbiology and Immunology - October 23, 2015 Category: Microbiology Authors: J.A. Hutcherson, H. Gogeneni, D. Yoder‐Himes, E.L. Hendrickson, M. Hackett, M. Whiteley, R.J. Lamont, D.A. Scott Tags: Original Article Source Type: research
Comparison of inherently essential genes of Porphyromonas gingivalis identified in two transposon ‐sequencing libraries
Summary
Porphyromonas gingivalis is a Gram‐negative anaerobe and keystone periodontal pathogen. A mariner transposon insertion mutant library has recently been used to define 463 genes as putatively essential for the in vitro growth of P. gingivalis ATCC 33277 in planktonic culture (Library 1). We have independently generated a transposon insertion mutant library (Library 2) for the same P. gingivalis strain and herein compare genes that are putatively essential for in vitro growth in complex media, as defined by both libraries. In all, 281 genes (61%) identified by Library 1 were common to Library 2. Many of these ...
Source: Oral Microbiology and Immunology - October 22, 2015 Category: Microbiology Authors: J.A. Hutcherson, H. Gogeneni, D. Yoder ‐Himes, E.L. Hendrickson, M. Hackett, M. Whiteley, R.J. Lamont, D.A. Scott Tags: Original Article Source Type: research
Dental caries – not just holes in teeth! A perspective
Summary
Cavitation in teeth results from a pathogenic process termed dental caries that has occurred on the tooth surface for weeks or even years. Accumulation of dental plaque (biofilm) on the tooth is usually the first manifestation of the disease. Although acid production is the immediate and proximal cause of dissolution of teeth; it is the milieu within which the acid is formed that should be of primary concern. Focusing on the ‘critical pH’ has detracted attention from the more biological aspects (biofilm formation) of dental caries. Dental caries is unique; it is a biological process occurring on essentially an ...
Source: Oral Microbiology and Immunology - October 12, 2015 Category: Microbiology Authors: W.H. Bowen Tags: Invited Review Source Type: research
D‐alanine Metabolism is Essential for Growth and Biofilm Formation of Streptococcus mutans
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Source: Oral Microbiology and Immunology - October 1, 2015 Category: Microbiology Authors: Wei Qiu, Xin Zheng, Yuan Wei, Xuedong Zhou, Keke Zhang, Shida Wang, Lei Cheng, Yan Li, Biao Ren, Xin Xu, Yuqing Li, Mingyun Li Tags: Original Article Source Type: research
Escape from the competence state in Streptococcus mutans is governed by the bacterial population density
This article is protected by copyright. All rights reserved. (Source: Oral Microbiology and Immunology)
Source: Oral Microbiology and Immunology - October 1, 2015 Category: Microbiology Authors: D. Dufour, C. Villemin, J.A. Perry, C.M. Lévesque Tags: Original Article Source Type: research
T cells, teeth and tissue destruction – what do T cells do in periodontal disease?
This article is protected by copyright. All rights reserved. (Source: Oral Microbiology and Immunology)
Source: Oral Microbiology and Immunology - October 1, 2015 Category: Microbiology Authors: Lauren Campbell, Emma Millhouse, Jennifer Malcolm, Shauna Culshaw Tags: Invited Review Source Type: research
Secreted ATP from A. actinomycetemcomitans triggers chemokine response
This article is protected by copyright. All rights reserved. (Source: Oral Microbiology and Immunology)
Source: Oral Microbiology and Immunology - October 1, 2015 Category: Microbiology Authors: Qinfeng Ding, Samantha Yiling Quah, Kai Soo Tan Tags: Original Article Source Type: research
Sublingual immunization with the phosphate binding‐protein (PstS) reduces oral colonization by Streptococcus mutans
This article is protected by copyright. All rights reserved. (Source: Oral Microbiology and Immunology)
Source: Oral Microbiology and Immunology - October 1, 2015 Category: Microbiology Authors: Ewerton Lucena Ferreira, Milene Tavares Batista, Rafael Ciro Marques Cavalcante, Vanessa Rodrigues Pegos, Hélic Moreira Passos, Dalva Adelina da Silva, Andrea Balan, Luís Carlos de Souza Ferreira, Rita de Cássia Café Ferreira Tags: Original Article Source Type: research
Variants of Porphyromonas gingivalis lipopolysaccharide alter lipidation of autophagic protein, microtubule–associated protein 1 light chain 3, LC3
This article is protected by copyright. All rights reserved. (Source: Oral Microbiology and Immunology)
Source: Oral Microbiology and Immunology - October 1, 2015 Category: Microbiology Authors: Ignacio Blasi, Jonathan Korostoff, Anuradha Dhingra, Juan Reyes‐Reveles, Bruce J. Shenker, Nishat Shahabuddin, Desiree Alexander, Edward T. Lally, Alvina Bragin, Kathleen Boesze‐Battaglia Tags: Original Article Source Type: research
