The reductive dechlorination of 2,3,4,5-tetrachlorobiphenyl in three different sediment cultures: evidence for the involvement of phylogenetically similar Dehalococcoides-like bacterial populations.
The reductive dechlorination of 2,3,4,5-tetrachlorobiphenyl in three different sediment cultures: evidence for the involvement of phylogenetically similar Dehalococcoides-like bacterial populations.
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DOI：
10.1111/j.1574-6941.2005.00022.x
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发表时间：
2006-02
影响因子：
4.2
通讯作者：
T. Yan;T. LaPara;P. Novak
中科院分区：
文献类型：
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作者：
T. Yan;T. LaPara;P. Novak
从三种不同的沉积物中富集了能够还原脱氯2，3，4，5-四氯联苯（CB）的厌氧培养物，一个河口，一个海洋和一个河流。两种不同的电子供体被用于富集与河口沉积物（元素铁或脂肪酸的混合物）。在所有培养物中观察到双侧翼Meta和帕拉氯的去除以形成2，3，5-CB和2，4，5-CB。PCR扩增的16 S rRNA基因片段的细菌群落分析揭示了不同的社区在这些文化中，除了一个共同的人口，表现出较高的同源性Dehalococcoides物种。没有Dehalocococcoides样人群中检测到的控制文化，没有多氯联苯添加。此外，这类Dehalocococcoides种群的动态与脱氯密切相关。河口沉积物培养的继代培养表明，Dehalocococcoides样人口消失时，脱氯抑制与2-溴乙磺酸盐或当2，3，4，5-CB已被消耗。这些结果提供的证据表明，Dehalococcoides样人口参与了双侧翼氯从2，3，4，5-CB的去除。此外，从地理上遥远和地球化学上不同的环境中成功富集这些种群表明，这些多氯联苯脱氯，Dehalococcoides样生物的广泛存在。
Anaerobic cultures capable of reductively dechlorinating 2,3,4,5-tetrachlorobiphenyl (CB) were enriched from three different sediments, one estuarine, one marine and one riverine. Two different electron donors were used in enrichments with the estuarine sediment (elemental iron or a mixture of fatty acids). The removal of doubly flanked meta and para chlorines to form 2,3,5-CB and 2,4,5-CB was observed in all cultures. Bacterial community analysis of PCR-amplified 16S rRNA gene fragments revealed different communities in these cultures, with the exception of one common population that showed a high phylogentic relatedness to Dehalococcoides species. No Dehalococcoides-like populations were ever detected in control cultures to which no PCBs were added. In addition, the dynamics of this Dehalococcoides-like population were strongly correlated with dechlorination. Subcultures of the estuarine sediment culture demonstrated that the Dehalococcoides-like population disappeared when dechlorination was inhibited with 2-bromoethanesulfonate or when 2,3,4,5-CB had been consumed. These results provide evidence that Dehalococcoides-like populations were involved in the removal of doubly flanked chlorines from 2,3,4,5-CB. Furthermore, the successful enrichment of these populations from geographically distant and geochemically distinct environments indicates the widespread presence of these PCB-dechlorinating, Dehalococcoides-like organisms.