Editor: Alfons Stams
Evidence for syntrophic butyrate metabolism under sulfate-reducing conditions in a hydrocarbon-contaminated aquifer
Article first published online: 1 FEB 2011
© 2011 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved
FEMS Microbiology Ecology
Volume 76, Issue 2, pages 289–300, May 2011
How to Cite
Struchtemeyer, C. G., Duncan, K. E. and McInerney, M. J. (2011), Evidence for syntrophic butyrate metabolism under sulfate-reducing conditions in a hydrocarbon-contaminated aquifer. FEMS Microbiology Ecology, 76: 289–300. doi: 10.1111/j.1574-6941.2011.01046.x
- Issue published online: 8 APR 2011
- Article first published online: 1 FEB 2011
- Accepted manuscript online: 11 JAN 2011 09:01AM EST
- Received 20 September 2010; revised 16 November 2010; accepted 1 January 2011., Final version published online 1 February 2011.
The importance of syntrophy in the degradation of butyrate in an aquifer where sulfate reduction was shown to be an important terminal electron-accepting process was assessed. Hydrocarbon-contaminated aquifer sediments coupled butyrate degradation to sulfate reduction and methane production. Butyrate degradation in methanogenic microcosms was inhibited by the addition of 2-bromoethanesulfonic acid, and was restored by the addition of 10 mM sulfate and a hydrogen- and formate-using sulfate reducer, but not by the addition of 10 mM sulfate alone. Molybdate addition inhibited butyrate degradation in sulfate-reducing microcosms. The addition of CO, which inhibits hydrogenases, to sulfate-reducing microcosms inhibited butyrate metabolism and caused the hydrogen partial pressure to increase to levels that would make syntrophic butyrate degradation via sulfate reduction energetically unfavorable (−5 to +3 kJ mol−1). DNA extracted from the most probable number cultures and contaminated sediments contained sequences related to members of the families Syntrophomonadaceae and Syntrophaceae, whose members are known to syntrophically degrade fatty acids, as well as sequences related to uncultured Firmicutes, Desulfobulbaceae, Desulfobacteriaceae, and Desulfovibrionaceae. These data show that contaminated sediments degraded butyrate syntrophically coupled to methane production and sulfate reduction.