Project description:Little is known about the bacteria that reside in human gallbladder and the mechanisms that allow them to survive within this harsh environmental niche. Furthermore, certain bacterial species are considered to exhibit antagonistic activities whilst others may form mutualistic interactions through, for example, cross-feeding. We isolated two new strains from healthy human bile samples, one belonging to Ruminococcus gauvreauii, of Lachnospiraceae family, and other constituting a new specie in Ruminococcaceae family, named Ruminocoides biliarensis. The two strains differed markedly in their carbohydrate metabolism as R. gauvreauii mainly metabolised sugar alcohols, including inositol, to form acetate as unique fermentation product, and Rc. biliarensis mainly metabolised resistant starches to mainly form formate and acetate as fermentation end products. Both strains exhibited resistance to different bile salts, and the ability to sporulate. Amino acid and vitamin biosynthesis profiles also markedly differed between the two bile isolates. Finally,RNAseq was used to analyse the co-cultures of both isolates, to analyze the activities involved in the possible cross-feeding relationship.
Project description:We performed a transcriptome analysis of Ruminococcus gnavus with and without 0.1% (w/w) agarooligosaccharide exposure to validate the mechanism of growth inhibition.
Project description:This study compares growth of Ruminococcus flavefaciens FD-1 with cellulose or cellobiose as the carbohydrate substrate. Ruminococcus flavefaciens is a predominant cellulolytic rumen bacterium, which forms a multi-enzyme cellulosome complex that could play an integral role in the ability of this bacterium to degrade plant cell wall polysaccharides. Identifying the major enzyme types involved in plant cell wall degradation is essential for gaining a better understanding of the cellulolytic capabilities of this organism as well as highlighting potential enzymes for application to improvement of livestock nutrition and for conversion of cellulosic biomass to liquid fuels. These results show that the growth substrate drives expression of enzymes predicted to be involved in carbohydrate metabolism as well as expression and assembly of key cellulosomal enzyme components. 1 species (Ruminococcus flavefaciens FD_1), 2 conditions (cellulose, cellobiose), 4 biological replicates. Direct design with biological dye swap.
Project description:This study compares growth of Ruminococcus flavefaciens FD-1 with cellulose or cellobiose as the carbohydrate substrate. Ruminococcus flavefaciens is a predominant cellulolytic rumen bacterium, which forms a multi-enzyme cellulosome complex that could play an integral role in the ability of this bacterium to degrade plant cell wall polysaccharides. Identifying the major enzyme types involved in plant cell wall degradation is essential for gaining a better understanding of the cellulolytic capabilities of this organism as well as highlighting potential enzymes for application to improvement of livestock nutrition and for conversion of cellulosic biomass to liquid fuels. These results show that the growth substrate drives expression of enzymes predicted to be involved in carbohydrate metabolism as well as expression and assembly of key cellulosomal enzyme components.
