Biochemical and genetic bases of dehalorespiration
Biochemical and genetic bases of dehalorespiration
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DOI：
10.1002/tcr.20134
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发表时间：
2008-01-01
期刊：
影响因子：
6.6
通讯作者：
Furukawa, Kensuke
中科院分区：
文献类型：
--
作者：
Futagami, Taiki;Goto, Masatoshi;Furukawa, Kensuke
一些厌氧细菌可以通过还原脱卤化有效地消除卤代化合物中的一个或多个卤化物原子，如氯酚和氯乙烯。在这个过程中，细菌利用卤化化合物作为其厌氧呼吸的末端电子受体，称为脱卤素呼吸，以产生生长所需的能量。目前，脱盐细菌属和脱卤球菌属占脱盐呼吸菌株的主要部分。前者不仅可以通过脱卤素呼吸获得能量，还可以通过利用有机化合物和金属的其他呼吸获得能量。与之形成鲜明对比的是，后者专门从事脱卤素呼吸，在自然界中氯化化合物的解毒中起着至关重要的作用。从这些细菌中提纯了催化脱卤化反应的各种还原脱卤酶，并鉴定了相应的基因。大多数还原脱卤酶表现出类似的特征，例如存在一个TAT(双精氨酸转位)信号序列，两个Fe-S簇和一个皮质醇辅因子。一些脱卤酶编码基因被发现位于插入序列的两侧。因此，脱卤酶基因起到分解代谢转座子的作用，在脱卤型呼吸器中，由转座元件介导的基因重排发生得很好。此外，一些脱盐呼吸细菌的基因组序列为了解脱盐呼吸的机制和清卤酶基因的进化提供了许多见解。(C)2008年日本化学期刊论坛和威利期刊公司。
Some anaerobic bacteria can efficiently eliminate one or more halide atoms from halogenated compounds such as chlorophenols and chloroethenes through reductive dehalogenation. During this process, the bacteria utilize halogenated compounds as the terminal electron acceptors in their anaerobic respiration, called dehalorespiration, to yield energy for growth. Currently the genera of Desulfitobacterium and Dehalococcoides occupy the major part of the dehalorespiring isolates. The former can acquire energy not only by dehalorespiration but also by other respirations utilizing organic compounds and metals. In sharp contrast, the latter is specialized in dehalorespiration and plays a crucial role in the detoxification of chlorinated compounds in nature. From these bacteria, various reductive dehalogenases, which catalyze the dehalogenation reaction, were purified and their corresponding genes were identified. Most reductive dehalogenases exhibit similar features such as the presences of a Tat (twin arginine translocation) signal sequence, two Fe-S clusters, and a corrinoid cofactor. Some of dehalogenase-encoding genes are found to be flanked by insertion sequences. Thus, dehalogenase genes act as a catabolic transposon, and genetic rearrangements mediated by transposable elements occur well in dehalorespirers. Moreover, the genome sequences of some dehalorespiring bacteria provide many insights into the mechanism of dehalorespiration and the evolution of a clehalogenase gene. (c) 2008 The Japan Chemical journal Forum and Wiley Periodicals, Inc.