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
Project description:Periodontal diseases are one of the most common human maladies and appear to be caused by the interaction of proximal pathogens such as Porphyromonas gingivalis but only as part of the polymicrobial community known as dental plaque. Streptococcus gordonii is an early colonizing oral organism that binds to oral surfaces and provides adherence for organisms such as P. gingivalis. Together P. gingivalis and S. gordonii form one of the simplest models of potentially pathogenic dental plaque. We used RNA sequencing to monitor the transcriptome of P. gingivalis over time in a biofilm model both in the presence and absence of S. gordonii. Samples were taken at 5, 30, 120, 240, and 360 minutes after shifing from planktonic to sessile conditions and growth media to PBS. When compared to planktonic cells increased transcripts were found for stress, amino acid catabolism, and comeptence and decreased transcripts for DNA replication. The presence of S. gordonii resulted in fewer changes from planktonic cells implying physiological support to Pl gingivalis making the transition from planktonic to sessile easier.
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.
Project description:Wild type Porphyromonas gingivalis strain ATCC33277 (V3176) and PG1626 - deficient mutant (V3177) were grown in iron replete conditions was used to compare to Porphyromonas gingivalis strains grown in iron chelated conditions.
Project description:Rgg-dependent transcriptional regulation in SF370 Streptococcus pyogenes strain was analyzed during post-exponential phase of growth Keywords: rgg mutant