title: Study of constancy of hydrogen-consuming flora of human colon.
abstract: The constancy of the hydrogen consuming flora of the human colon was studied in 15 healthy subjects via two measurements obtained 18 to 36 months apart. Hydrogen disappearance rate and the major products of H2-consuming bacteria, methane and sulfide, were measured during incubation of fecal homogenates with excess hydrogen and sulfate. In 11/15, the hydrogen consumption rate and the predominant hydrogen-consuming pathway (methanogenesis, sulfate reduction, or neither) remained constant. However, major shifts in these pathways were observed in four subjects, with two losing and two gaining the ability to produce methane. Methanogenesis was associated with the highest hydrogen consumption rate. This study demonstrates that clinically unrecognizable, major alterations of the colonic flora occur in healthy subjects. Understanding of the factors responsible for these alterations might allow for therapeutic manipulation of the colonic flora.
authors.affiliation: Minneapolis VA Medical Center, Minnesota 55417.
authors.forename: A
authors.initials: A
authors.lastname: Strocchi
authors.forename: C J
authors.initials: CJ
authors.lastname: Ellis
authors.forename: J K
authors.initials: JK
authors.lastname: Furne
authors.forename: M D
authors.initials: MD
authors.lastname: Levitt
mesh_terms: D001419:Bacteria / Q000378:metabolism*; D003106:Colon / Q000382:microbiology*; D006801:Humans; D006859:Hydrogen / Q000378:metabolism*; D008697:Methane / Q000378:metabolism; D013440:Sulfides / Q000378:metabolism
chemical_list: D013440:Sulfides; D006859:Hydrogen; D008697:Methane