Stable-isotope probing of microorganisms thriving at thermodynamic limits: syntrophic propionate oxidation in flooded soil.

ABSTRACT: Propionate is an important intermediate of the degradation of organic matter in many anoxic environments. In methanogenic environments, due to thermodynamic constraints, the oxidation of propionate requires syntrophic cooperation of propionate-fermenting proton-reducing bacteria and H(2)-consuming methanogens. We have identified here microorganisms that were active in syntrophic propionate oxidation in anoxic paddy soil by rRNA-based stable-isotope probing (SIP). After 7 weeks of incubation with [(13)C]propionate (<10 mM) and the oxidation of approximately 30 micromol of (13)C-labeled substrate per g dry weight of soil, we found that archaeal nucleic acids were (13)C labeled to a larger extent than those of the bacterial partners. Nevertheless, both terminal restriction fragment length pol

SUBMITTER: Lueders T 

PROVIDER: S-EPMC522077 | biostudies-literature | 2004 Oct

REPOSITORIES: biostudies-literature