This manuscript has been previously published as Chapter 3 of Duhamel, MA (2005) Community structure and dynamics of anaerobic chlorinated ethene-degrading enrichment cultures, pp. 21–66. Ph.D. Thesis, Department of Chemical Engineering and Applied Chemistry, University of Toronto.
Microbial composition of chlorinated ethene-degrading cultures dominated by Dehalococcoides
Article first published online: 18 AUG 2006
FEMS Microbiology Ecology
Volume 58, Issue 3, pages 538–549, December 2006
How to Cite
Duhamel, M. and Edwards, E. A. (2006), Microbial composition of chlorinated ethene-degrading cultures dominated by Dehalococcoides. FEMS Microbiology Ecology, 58: 538–549. doi: 10.1111/j.1574-6941.2006.00191.x
Editor: Max Häggblom
- Issue published online: 18 AUG 2006
- Article first published online: 18 AUG 2006
- Received 9 February 2006; revised 12 June 2006; accepted 13 June 2006.First published online 18 August 2006.
- reductive dechlorination;
- vinyl chloride;
- quantitative PCR;
- functional redundancy
The community composition of microbial cultures degrading tetrachloroethene (PCE), trichloroethene (TCE), cis-1,2-dichloroethene (cDCE) and vinyl chloride (VC) to ethene was studied. A combination of PCR-denaturing gradient gel electrophoresis (PCR-DGGE) and 16S rRNA gene sequence analysis revealed that all cultures contained Dehalococcoides populations, but that the populations of other organisms varied widely. Based on the sequences of cloned 16S rRNA genes, real-time PCR methods were developed for several of these phylotypes affiliated with the putative dechlorinators Sulfurospirillum and Geobacter, the putative methanogens Methanomethylovorans, Methanomicrobiales, Methanosaeta and Methanosarcina, the putative acetogens Acetobacterium, Spirochaetes, and Sporomusa, and the putative fermenters Bacteroidetes, Syntrophus, and Syntrophobacter. These novel quantitative PCR methods were then used to estimate relative abundances of each phylotype in several individual cultures maintained on each chlorinated ethene. Dehalococcoides populations were the dominant phylotypes assayed in most KB-1 cultures, agreeing with the DGGE and cloning results. A Geobacter phylotype was also strongly represented in most PCE and TCE cultures, but not in cDCE or VC cultures, suggesting a possible role for this organism as a PCE-to-cDCE dechlorinator. The Sulfurospirillum phylotype was estimated to comprise a minor fraction of 16S rRNA gene copies and did not appear to have an important role in dechlorination.