title: Mechanisms of microbial hydrogen disposal in the human colon and implications for health and disease.
abstract: In the human gastrointestinal tract, dietary components, including fiber, that reach the colon are fermented principally to short-chain fatty acids, hydrogen, and carbon dioxide. Microbial disposal of the hydrogen generated during anaerobic fermentation in the human colon is critical to optimal functioning of this ecosystem. However, our understanding of microbial hydrogenotrophy is fragmented and, at least as it occurs in the colon, is mostly theoretical in nature. Thorough investigation and integration of knowledge on the diversity of hydrogenotrophic microbes, their metabolic variation and activities as a functional group, as well as the nature of their interactions with fermentative bacteria, are necessary to understand hydrogen metabolism in the human colon. Here, we review the limited data available on the three major groups of H(2)-consuming microorganisms found in the human colon [methanogens, sulfate-reducing bacteria (SRB), and acetogens] as well as evidence that end products of their metabolism have an important impact on colonic health.
authors: Department of Animal Sciences and Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.
authors: Noriko
authors: N
authors: Nakamura
authors: Henry C
authors: HC
authors: Lin
authors: Christopher S
authors: CS
authors: McSweeney
authors: Roderick I
authors: RI
authors: Mackie
authors: H Rex
authors: HR
authors: Gaskins
mesh_terms: D019342:Acetic Acid / Q000009:adverse effects / Q000378:metabolism; D003106:Colon / Q000382:microbiology*; D015179:Colorectal Neoplasms / Q000453:epidemiology / Q000382:microbiology; D006801:Humans; D006859:Hydrogen / Q000378:metabolism*; D015212:Inflammatory Bowel Diseases / Q000453:epidemiology / Q000382:microbiology; D008697:Methane / Q000009:adverse effects / Q000378:metabolism; D017018:Methanomicrobiales / Q000378:metabolism*; D009765:Obesity / Q000453:epidemiology / Q000382:microbiology; D016999:Sulfur-Reducing Bacteria / Q000378:metabolism*
chemical_list: D006859:Hydrogen; D008697:Methane; D019342:Acetic Acid