Location: Agroecosystems Management ResearchTitle: Remarkable similarity among bacteria isolated from four hosts after eight-week enrichments of feces with cellulose and xylan/pectin Author
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 4/17/2013
Publication Date: 4/17/2013
Citation: Ziemer, C.J. 2013. Remarkable similarity among bacteria isolated from four hosts after eight-week enrichments of feces with cellulose and xylan/pectin. In: Proceedings of the 2013 Congress on Gastrointestinal Function. Interpretive Summary:
Technical Abstract: The intestinal microbiota allows mammals to recover energy stored in plant biomass through fermentation of plant cell walls, primarily cellulose and hemicellulose. Bacteria were isolated from 8-week continuous culture enrichments with cellulose and xylan/pectin from cow (n=4), goat (n=4), human (n=4), and pig (n=6) feces. 16S rRNA genes were sequenced (ISU DNA Sequencing and Synthesis Facility) and analyzed using Bionumerics software. Bacteria isolated from the same fermenter with = 99% 16S rRNA gene sequence similarity were removed in order to reduce redundancy and simplify the data set; 462 cow, 363 goat, 255 human, and 575 pig isolates were included in the analyses. Of the cow and goat isolates, ~50% were < 95% and ~30% 95% > < 97% similar to cultured bacteria in the RDP-II, indicating limited available information on large intestinal microbiota in these ruminants. Although culture methods introduce some bias, bacteria isolated across hosts were remarkably similar, in both numbers and species. Firmicutes and Bacteroidetes were the dominant phyla represented and made up 52.2% and 30.7% in cow, 43.5% and 34.2% in goat, 42.8% and 34.9% in human, and 41.9% and 32.0% in pig isolates. Other phyla represented included Proteobacteria (11.3% cow, 9.6% goat, 21.2% human, and 11.3% pig), Actinobacteria (3.5% cow, 4.7% goat, 1.2% human, and 4.0% pig), Fusobacteria (1.1% cow, 8.26% goat, and 9.6% pig), and Synergistetes (1.5% cow and 0.9% pig). While the number of isolates recovered from each carbohydrate source was similar, the distribution of isolates within phyla differed by carbohydrate type. Phylogenetic clustering by host, at the level of bacterial species, was not common. The greatest bacterial species differentiation by host was found in the Firmicutes. Future research will compare enriched microbiota metagenomes to isolations. These results indicate that members of distal large intestinal microbial communities have been conserved, by bacterial species, across mammals.