Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON, Canada.
Appl Environ Microbiol. 2012 Aug;78(15):5280-7. doi: 10.1128/AEM.00384-12. Epub 2012 May 25.
The WBC-2 consortium is an organohalide-respiring anaerobic microbial enrichment culture capable of dechlorinating 1,1,2,2-tetrachloroethane (TeCA) to ethene. In the WBC-2 culture, TeCA is first transformed to trans-dichloroethene (tDCE) by dichloroelimination; tDCE is subsequently transformed to vinyl chloride (VC) and then to ethene by hydrogenolysis. Analysis of 16S rRNA gene clone libraries from culture DNA revealed sequences from three putative dechlorinating organisms belonging to Dehalococcoides, Dehalobacter, and Dehalogenimonas genera. Quantitative PCR primers were designed for each of these sequences, and their abundance was quantified in enrichment cultures over time. These data revealed that complete dechlorination of TeCA to ethene involves all three organisms. Dehalobacter spp. grew during the dihaloelimination of TeCA to tDCE, while Dehalococcoides and Dehalogenimonas spp. grew during hydrogenolysis of tDCE to ethene. This is the first time a genus other than Dehalococcoides has been implicated in dechlorination of tDCE to VC.
WBC-2 联合体是一种能够将 1,1,2,2-四氯乙烷（TeCA）脱氯为乙烯的有机卤化物呼吸厌氧微生物富集培养物。在 WBC-2 培养物中，TeCA 首先通过二氯消除转化为反式-二氯乙烯（tDCE）；tDCE 随后通过氢解转化为氯乙烯（VC），然后转化为乙烯。对来自培养物 DNA 的 16S rRNA 基因克隆文库的分析揭示了属于 Dehalococcoides、Dehalobacter 和 Dehalogenimonas 属的三种假定脱氯生物体的序列。为每个序列设计了定量 PCR 引物，并随着时间的推移在富集培养物中定量其丰度。这些数据表明，TeCA 完全脱氯为乙烯涉及所有三种生物体。Dhalobacter spp. 在 TeCA 到 tDCE 的二卤消除过程中生长，而 Dehalococcoides 和 Dehalogenimonas spp. 在 tDCE 到乙烯的氢解过程中生长。这是首次有除 Dehalococcoides 属以外的属被牵连到 tDCE 到 VC 的脱氯反应中。
