Project description:Bifidobacterium longum subsp. infantis is a bacterial commensal that colonizes the breast-fed infant gut where it utilizes indigestible components delivered in human milk. Accordingly, human milk contains several non-protein nitrogenous molecules, including urea at high abundance. This project investigates the degree to which urea is utilized as a primary nitrogen source by Bifidobacterium longum subsp. infantis and incorporation of hydrolysis products into the expressed proteome.
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.
Project description:The purpose of this project was to determine the whole transcriptome response of Bifidobacterium longum subsp. infantis to human milk urea compared to complex nitrogen and L-cysteine.
Project description:The purpose of this project was to determine the whole transcriptome response of Bifidobacterium longum subsp. Infantis to pooled and individual human milk oligosaccharides (HMO) relative to lactose