The history of anaerobic microbial polychlorinated biphenyl (PCB) dechlorination is traced over 20 years using a case study of PCB dechlorination in the Housatonic River (Massachusetts) as an example. The history progresses from the characterization of the PCBs in the sediment, to cultivation in sediment microcosms, to the identification of four distinct types of PCB dechlorination, to a successful field test, to the cultivation in defined medium of the organisms responsible for extensive dechlorination of Aroclor 1260, and finally to the identification of a Dehalococcoides population that links its growth to the dechlorination of Aroclor 1260. Other PCB dechlorinators have also been identified. Two bacterial strains, o-17 and DF-1, that link their growth to the dechlorination of several PCB congeners belong to a novel clade of putative dechlorinating bacteria within the phylum Chloroflexi. Dehalococcoides ethenogenes strain 195 also dechlorinates several PCB congeners when grown on chlorinated ethenes. Evidence is mounting that Dehalococcoides and other dechlorinating Chloroflexi may play a significant role in the dechlorination of commercial PCBs in situ.

中文翻译：

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微生物生物降解的案例研究：多氯联苯的厌氧细菌还原性脱氯-从沉积物到确定的介质。

以胡萨托尼克河（马萨诸塞州）的PCB脱氯为例，追溯了20年间厌氧微生物多氯联苯（PCB）脱氯的历史。历史从沉积物中多氯联苯的表征到沉积物微观世界的培养，再到四种不同类型的多氯联苯脱氯的鉴定，再到成功的田间试验，再到负责广泛脱氯的有机物在确定的培养基中的培养。 Aroclor 1260，最后是对将其生长与Aroclor 1260脱氯联系起来的Dehalococcoides种群的鉴定。还发现了其他PCB脱氯剂。两种细菌菌株o-17和DF-1，将它们的生长与几种PCB同类物质的脱氯联系起来的，属于叶绿菌门内的新型假定脱氯细菌进化枝。当在氯化乙烯上生长时，脱卤代球菌埃氏菌菌株195还可以脱除几种PCB同类物。越来越多的证据表明，Dehalococcoides和其他除氯的Chloroflexi可能在原位商业PCB的除氯中起重要作用。