Abstarct
The longterm goals of my laboratory are to elucidate mechanisms used by members of the intestinal microbiota to establish and maintain symbiotic relationships in the mammalian intestine. We study the Bacteroides species, which are the most abundant Gram-negative bacteria of this ecosystem, in some people accounting for 20% of the total intestinal bacteria. One active area of study in the lab is analysis of the synthesis, regulation, and significance of the enormous number of glycosylated molecules made by these bacteria. Our laboratory is also investigating other molecular mechanisms unique to these bacteria that contribute to their predominance in the complex and competitive human intestinal ecosystem. We are studying defensive strategies these bacteria may employ to protect themselves from harmful products produced by the host and other intestinal members, as well as offensive mechanisms they may use to thwart competitors. In this talk, I will present data on cooperative interactions such as glycan sharing (public goods production), competitive interactions by the production of secreted antimicrobial molecules, and evidence of DNA transfer between organisms within a human gut.
Laurie E. Comstock
Harvard Medical School