Monday, July 27, 2009 - 8:30 AM
S8
Metagenomic exploration of the termite hindgut
Phil Hugenholtz, Martin Allgaier, and Eddy Rubin. Joint Genome Institute, 2800 Mitchell Drive, Walnut Creek, CA 94598
Termites, with their complex hindgut microbiota, play significantglobal roles in the conversion of wood lignocellulose into carbondioxide and methane. We performed a metagenomic analysis of the microbial community resident in the luminal contents of the majorhindgut paunch, proctodeal segment 3 (P3), of a drywood-feeding Nasutitermes species. The dominant phylogenetic groups present in thegut were treponeme spirochetes and fibrobacters. Both groups were discovered to encode a large and diverse set of genes associated withsaccharification, in particular cellulose and xylan hydrolysis. Many of these genes were expressed in vivo and had cellulase activity in vitro, further implicating the bacterial community in lignocellulose degradation.
More recently we have begun investigating the alkaline P1 segmentupstream from the neutral pH P3 segment. This region habors a small community in the ectoperiotrophic space, quite distinct from the P3 community, consisting of a handful of Gram-positive populations belonging to the Firmicutes and Actinobacteria. I will present preliminary data from a metagenomic analysis of whole-genome amplified DNA extracted from this region.