Project description:Investigation of partial genome gene expression level changes in a Desulfovibrio africanus during exponential and stationary phase growth in the presence and absence of 5 ug/L Hg2+ (as HgNO3). Desulfovibrio africanus is a known mercury methylating bacteria
Project description:Investigation of partial genome gene expression level changes in a Desulfovibrio africanus during exponential and stationary phase growth in the presence and absence of 5 ug/L Hg2+ (as HgNO3). Desulfovibrio africanus is a known mercury methylating bacteria A 3 chip study using total RNA recovered from three separate cultures of Desulfovibrio africanus with 5 ug/L Hg during exponential phase growth, three seperate cultures of Desulfovibrio africanus with 5 ug/L Hg during stationary phase growth, three cultures of Desulfovibrio africanus without Hg during exponential phase growth, and Desulfovibrio africanus without Hg during stationary phase growth. Each chip measures the expression level of 4,585 genes and intergenic regions from Desulfovibrio africanus strain Walvis Bay on a custom Nimblegen format with 75-mer probes with tiled in 4-plex format.
Project description:Streptococcus gallolyticus subsp. gallolyticus is a commensal of the human gastrointestinal tract and a pathogen of infective endocarditis and other biofilm-associated infections with exposed collagen. Therefore, this study focuses on the characterization of the biofilm formation and collagen adhesion of S. gallolyticus subsp. gallolyticus under different conditions. It has been observed that lysozyme triggers biofilm formation divergently in the analyzed S. gallolyticus subsp. gallolyticus strains. The transcriptome analysis was performed for two strains which form more biofilm in the presence of lysozyme. Lysozyme leads to higher expression of genes of transcription and translation, of the dlt operon (cell wall modification), of hydrogen peroxide resistance proteins and of two immunity proteins which could be involved in biofilm formation. Furthermore, the adhesion ability of 73 different S. gallolyticus subsp. gallolyticus strains to collagen type I and IV was analyzed. High adhesion ability was observed for the strain UCN 34, whereas the strain DSM 16831 adhered only marginally to collagen. The full genome microarray analysis revealed strain-dependent gene expression due to adhesion. The expression of genes of a transposon and a phage region in strain DSM 16831 were increased, which corresponds to lateral gene transfer. Adherence to collagen leads to a change in the expression of genes of nutrients uptake in the strain UCN 34.