Comparative Genome Hybridization of Porphyromonas gingivalis strains
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ABSTRACT:
ORGANISM(S): Porphyromonas gingivalis
SUBMITTER: Emil Kozarov
PROVIDER: E-GEOD-18169 | biostudies-arrayexpress |
REPOSITORIES: biostudies-arrayexpress
Similar Datasets
Project description:Porphyromonas gingivalis and Treponema denticola are periodontalpathogens that are associated with the severity and progression of periodontal diseases. This study investigates the gene expression of Porphyromonas gingivalis during co-culture with Treponema denticola
2014-03-31 | E-MTAB-2214 | biostudies-arrayexpress
Project description:Porphyromonas gingivalis and Treponema denticola are periodontalpathogens that are associated with the severity and progression of periodontal diseases. this study investigates the gene expression of Treponema denticola during co-culture with Porphyromonas gingivalis.
2014-03-31 | E-MTAB-2257 | biostudies-arrayexpress
Project description:Transcriptional profiling of the wild-type and its htrA mutant. Identification of genes that are affected by the htrA mutation in P. gingivalis Keywords: Genetic modification Two-condition experiment, W83 vs. htrA mutant late-log growth phase. Biological replicates: 4 control, 4 mutant, independently grown. One replicate per array.
2010-05-26 | E-GEOD-10027 | biostudies-arrayexpress
Project description:Porphyromonas gingivalis is a major pathogen associated with the microbial biofilm-mediated disease chronic periodontitis. P. gingivalis has an obligate requirement for iron and protoporphyrin IX which it satisfies by transporting heme and iron liberated from the human host. The level of cellular iron in P. gingivalis affects the expression of a distinct iron-associated regulon of 64 genes and low iron invokes an iron sparing response. Iron homeostasis is usually mediated in Gram-negative bacteria at the transcriptional level by the Ferric Uptake Regulator (Fur). There is a single predicted P. gingivalis Fur superfamily orthologue named Har (heme associated regulator) that lacks the conserved metal binding residues found in other Fur orthologues. We show that Har binds both heme and ferrous iron resulting in a conformational change in the protein. Har was unable to complement the Escherichia coli H1780 fur mutant and there was no change in cellular metal content in a P. gingivalis Har mutant compared with the wild-type. The Har regulon of 44 genes is not predicted to play a role in iron homeostasis. Together these data indicated that Har does not regulate iron homeostasis in P. gingivalis. However, Har was required for heme-responsive biofilm development and its regulon overlapped P. gingivalis regulons previously identified after growth in heme limitation or as a homotypic biofilm. P. gingivalis is unique as an iron-dependent Gram-negative bacterium with a single heme-binding Fur superfamily orthologue, Har, that does not regulate iron homeostasis. Paired samples were compared on the same microarray using a two-colour system. A total of 6 paired microarray hybridizations were performed representing 6 biological replicates, where a balanced dye design was used, with the overall analysis including three microarrays where P. gingivalis 33277 samples were labeled with Cy3 and the paired ECR455 samples were labeled with Cy5 and three other microarrays where samples were labeled with the opposite combination of fluorophores.
2015-04-01 | E-GEOD-37099 | biostudies-arrayexpress
Project description:The aim of this experiment is to ascertain which genes have their expression influenced by PG1432. PG1432 encodes a putative sensor histidine kinase which is part of two component signal transduction that was highly up-regulated in P. gingivalis mature biofilm cells. PG1432 was disrupted in P. gingivalis W50 by insertion of ermF cassette. The strain W50 PG1432 mutant was designated ECR222. Two independent replicates of each strain were grown for 30 days in continuous culture in chemostats using brain heart infusion media supplemented with 0.5 mg mL-1 cysteine and 5 �~A�g mL-1 hemin. Although strain W50 formed sufficient biofilm to use for total RNA harvest and microarray analysis, strain ERC222 formed only sparse biofilm showing that disruption of PG1432 impaired biofilm formation by this mutant. We were unable to collect sufficient biofilm cells of strain ECR222 therefore the microarray analysis total RNAs were harvested only from planktonic phase cells. The transcriptome of the mutant ECR222 were compared to that of strain W50.
2010-01-11 | E-TABM-546 | biostudies-arrayexpress
Project description:Investigation of whole genome gene expression level changes in Porphyromonas gingivalis ATCC 33277 treated with an anti-adhesive extract from Myrothamnus flabellifolia compared to the untreated strain. Aim: Identification of anti-adhesive plant extracts against cell surface binding of Porphyromonas gingivalis. Materials and Methods: Polyphenol-enriched extract from Myrothamnus flabellifolia (MF) traditionally used for periodontitis was tested for inhibition of P. gingivalis adhesion to KB cells by FACS, for influence on gingipain activity, hemagglutination and by microarray analysis for effects on the bacterial transcriptome. P. gingivalis-induced inflammation parameters were monitored by RT-PCR. Results: MF (100 µg/ml) reduced P. gingivalis adhesion/invasion about 50% by interacting with fimbriae and bacterial OMPs. Microarray analysis of MF-treated bacteria indicated up-regulation of genes involved in cell adhesion. As confirmed by RT-PCR, fimbrillin- and Arg-gingipain-encoding genes were upregulated by MF. On the protein level, inhibition (70%) of Arg-gingipain activity was observed, while the corresponding Lys-gingipain was hardly influenced. MF also inhibited hemagglutination. While exposure to P. gingivalis resulted in an increased expression of inflammation-related genes in KB cells, pretreatment of KB cells with MF evoked cytoprotective effects concerning IL-1β, IL-6, IL-8 and TNFα gene expression as well as IL-6 release rates. Conclusions: While being cytoprotective, MF exerts strong anti-adhesive effects against P. gingivalis. Thus, MF may be useful for the prevention of P. gingivalis-associated periodontal diseases. The chip study used total RNA recovered from two separate MF-treated and two separate untreated Porphyromonas gingivalis ATCC 33277 cultures. Each chip measured the expression level of 1,842 genes from P. gingivalis ATCC 33277 with thirteen 60-mer probes per gene, with three-fold technical redundancy.
2010-09-02 | E-GEOD-23939 | biostudies-arrayexpress
Project description:Genotyping studies suggest that there is genetic variability among P. gingivalis strains, however the extent of variability remains unclear, and the regions of variability have only partially been identified. We previously used heteroduplex analysis of the ribosomal operon intergenic spacer region (ISR) to type P. gingivalis strains in several diverse populations, identifying 6 predominant heteroduplex types and many minor ones. In addition we used ISR sequence analysis to determine the relatedness of P. gingivalis strains to one another, and demonstrated a link between ISR sequence phylogeny and the disease-associated phenotype of P. gingivalis strains. The availability of whole genome microarrays based on the genomic sequence of strain W83 has allowed a more comprehensive analysis of P. gingivalis strain variability, using the entire genome. The objectives of this study were to define the phylogeny of P. gingivalis strains using the entire genome, to compare the phylogeny based on genome content to the phylogeny based on a single locus (ISR), and to identify genes that are associated with the strongly disease-associated strain W83 that could be important for virulence. Keywords: Comparative genomic hybridization Comparative genomic analysis of 7 clinically prevalent P. gingivalis strains was performed, using whole genome microarrays based on the sequence of strain W83. Strain W83 was the reference strains and there were 6 test strains. Flip-dye replicates were performed.
2010-05-18 | E-GEOD-13128 | biostudies-arrayexpress
Project description:Bistable populations of bacteria give rise to two or more subtypes that exhibit different phenotypes. We have explored whether the periodontal pathogen, Porphyromonas gingivalis, exhibits bistable invasive phenotypes. Using a modified cell invasion assay, we show for the first time that there are two distinct sub-types within a population of P.ginigivalis strains NCTC 11834 and W50 that display differences in their ability to invade oral epithelial cells. The highly-invasive sub-types invade cells at 10-30 fold higher levels than the poorly-invasive subtype and remain highly invasive for approximately 12-16 generations. Analysis of the gingipain activity of these sub-types revealed that the highly invasive type had reduced cell-associated arginine specific protease activity. The role of arg-gingipain activity in invasion was verified by enhancement of invasion by rgpAB mutations and by inclusion of an arg-gingipain inhibitor in invasion assays using wild-type bacteria. In addition a population of DeltargpAB bacteria did not contain a hyperinvasive sub-type. Screening of the protease activity of wild-type populations of both strains identified high and low protease sub-types which also showed the corresponding reduction or enhancement of invasive capabilities. Microarray analysis of these bistable populations revealed a putative signature set of genes that include oxidative stress resistance and iron transport genes that might be key to invasion of or survival within epithelial cells. Porphyromonas gingivalis comparison of Invasive V Non-invasive sub-types of NCTC11834 and W50 (samples 1-12 AND High V low protease subtypes (samples 13-24) Samples 1-3 were compared top 4-6 and 7-9 V 10-12 for invasive experiments and similarly for protease strain experiments
2010-08-31 | E-GEOD-23021 | biostudies-arrayexpress
Project description:Periodontitis is the most common human infection affecting tooth-supporting structures. It was shown to play a role in aggravating atherosclerosis. To deepen our understanding of the pathogenesis of this disease, we exposed human macrophages to an oral bacteria Porphyromonas gingivalis (P. gingivalis) either as live bacteria, or its lipopolysaccharide (LPS) or fimbria. Microarray data from treated macrophages or control cells were analyzed to define molecular signatures. We focused our analysis on three important groups of genes. Group PG (genes differentially expressed by live bacteria only); Group LFG (genes differentially expressed in response to exposure to LPS and/or FimA); Group CG (core gene set jointly activated by all 3 stimulants). A total of 842 macrophage genes were differentially expressed in at least one of the three conditions compared to naïve cells. Using pathway analysis, we found that group CG activates the initial phagocytosis process and induces genes relevant to immune response, whereas group PG can de-activate the phagocytosis process associated with phagosome-lysosome fusion. LFG mostly affected RIG-I-like receptor signaling pathway. 12 samples in total. 4 conditions (treatment with live P. gingivalis, P. gingivalis LPS, P. gingivalis fimbriae, or saline) were used, and triplicates were performed for each condition. We considered the following comparisons: PG vs. Control (saline), PG-LPS vs. Control, and PG-fimbriae vs. Control. Fold-change > 2.0 and FDR < 0.25 were used to select significantly expressed genes.
2010-10-23 | E-GEOD-24897 | biostudies-arrayexpress
Project description:High-density tiling microarray and RNA sequencing technologies were used to analyze the transcriptome of Porphyromonas gingivalis. The compiled P. gingivalis transcriptome were based on total RNA samples isolated from three different laboratory culturing conditions and the strand-specific transcription profiles generated covered the entire genome including both protein coding and non-coding regions. The transcription profiles revealed various operon structures, 5' and 3' end untranslated regions (UTRs), differential expression patterns, and several not-yet annotated transcripts within intergenic and antisense regions. Further transcriptome analysis identified the majority of the genes to be expressed within operons and most 5' and 3' ends to be protruding UTRs of which several 3M-CM-"M-BM-^@M-BM-^Y UTRs were extended to overlap genes encoded on the opposite/antisense strand. Extensive antisense RNAs were identified opposite to most of insertion sequence (IS) elements. With the growing realization that non-coding RNAs play important biological functions, the comprehensive transcriptome profiles compiled in this study are of great value for the further understanding of gene regulation and virulence mechanism in this periodontal pathogen. The transcriptome profiles can be viewed at and downloaded from the 'Microbial Transcriptome Database' web site http://bioinformatics.forsyth.org/mtd. 3 total RNA samples from growing P. gingivalis strain W83 under different media conditions subjected to RNA-Seq.
2011-10-01 | E-GEOD-30452 | biostudies-arrayexpress