Human Gut Teems with Over 1,000 Bacterial Species
Colon's microbiome produce enzymes required for vitamin and plant-sugar metabolism
THURSDAY, June 1 (HealthDay News) -- The human colon contains up to 100 trillion organisms representing over 1,000 species of bacteria, and they provide a host of genes necessary for the metabolism of vitamins, sugars and fiber, according to an analysis of the colon's microbiome published in a report in the June 2 issue of Science.
Steven R. Gill, formerly of The Institute for Genomic Research in Rockville, Md., now at the State University of New York at Buffalo, and colleagues conducted a metagenomic analysis of fecal samples collected from two anonymous healthy adults who had not received antibiotics or other medications in the year prior to study.
The researchers found evidence for several hundred bacterial phylotypes, mostly related to either the Firmicutes or Actinobacteria bacterial divisions or the methanogenic archaeon, Methanobrevibacter smithii. The collective microbiome was more diverse than those reported for environmental soil or sea samples and contained at least 100 times as many genes as the human genome, including many responsible for metabolism of vitamins and plant sugars like cellobiose.
"The results should provide a broader view of human biology, including new biomarkers for defining our health; new ways for optimizing our personal nutrition; new ways for predicting the bioavailability of orally administered drugs; and new ways to forecast our individual and societal predispositions to disorders such as infections with pathogens, obesity, and misdirected or maladapted host immune responses of the gut," the authors write.