Analysis of GI Community Shifts in Response to Dietary Fiber

To enhance survivability of military personnel with limited provisions, it may be possible to alter human gut bacterial populations to increase energy yield from plant fiber. To enable development of strategies to modify bacterial function for enhanced cellulose digestion, specific aims of the project were I) identify organisms in the pig that respond to cellulose, 2) compare these to what has been identified from humans, then 3) organisms that are cellulolytic and native (or closely related) to the human GI tract will be targeted for further characterization for future possible enhancement of fiber digestion. During this period we used comparative 163 rRNA gene sequence terminal restriction fragment length polymorphisms to identify bacteria of the swine cecum that increase in response to a high cellulose diet. The species of bacteria will be further identified from clone libraries of the 163 rRNA bacterial genes obtained from the swine cecum samples and compared to available human bacterial sequences. Preliminary sequencing has been completed and analysis of the species composition is in progress. For the next period we will complete analysis of a second diet trial, compare sequences to the available human bacterial sequences, and initiate culturing of cellulolytic bacteria native to the gut.
The original document contains color images. Prepared in cooperation with National Swine Research and Information Center, Swine Odor and Manure Management Research Unit, Ames, IA 50011-3310