Project description:The adult human gut microbial community is typically dominated by two bacterial phyla (divisions), the Firmicutes and the Bacteroidetes. Little is known about the factors that govern the interactions between their members. Here we examine the niches of representatives of both phyla in vivo. Finished genome sequences were generated from E. rectale and E. eligens, which belong to Clostridium Cluster XIVa, one of the most common gut Firmicute clades. Comparison of these and 25 other gut Firmicutes and Bacteroidetes indicated that the former possess smaller genomes and a disproportionately smaller number of glycan-degrading enzymes. Germ-free mice were then colonized with E. rectale and/or a prominent human gut Bacteroidetes, Bacteroides thetaiotaomicron, followed by whole genome transcriptional profiling of both organisms in their distal gut (cecal) habitat as well as host responses, high resolution proteomic analysis of cecal contents, and biochemical assays of carbohydrate metabolism. B. thetaiotaomicron adapts to E. rectale by upregulating expression of a variety of polysaccharide utilization loci (PULs) encoding numerous glycoside hydrolase gene families, and by signaling the host to produce mucosal glycans that it, but not E. rectale, can access. E. rectale adapts to B. thetaiotaomicron by decreasing production of its glycan-degrading enzymes, increasing expression of selected amino acid and sugar transporters, and facilitating glycolysis by reducing levels of NADH, in part via generation of butyrate from acetate, which in turn is utilized by the gut epithelium. This simplified model of the human gut microbiota illustrates niche specialization and functional redundancy within members of major gut bacterial phyla, and the importance of host glycans as a nutrient foundation that ensures ecosystem stability.

2009-03-01 | GSE14686 | GEO

Expression analysis of strains Lactococcus lactis KCTC 3769T, L. raffinolactis DSM 20443T, L. plantarum DSM 20686T, L. fujiensis JSM 16395T, L. garvieae KCTC 3772T, L. piscium DSM 6634T and L. chungangensis CAU 28T

Project description:Investigation of whole genome gene expression level changes in Lactococcus lactis KCTC 3769T,L. raffinolactis DSM 20443T, L. plantarum DSM 20686T, L. fujiensis JSM 16395T, L. garvieae KCTC 3772T, L. piscium DSM 6634T and L. chungangensis CAU 28T . This proves that transcriptional profiling can facilitate in elucidating the genetic distance between closely related strains.

2014-05-28 | GSE58002 | GEO

Project description:Treponema rectale draft genome

| PRJNA681240 | ENA