Identification and characterization of genes involved in the downstream degradation pathway of γ-hexachlorocyclohexane in Sphingomonas paucimobilis UT26
Identification and characterization of genes involved in the downstream degradation pathway of γ-hexachlorocyclohexane in Sphingomonas paucimobilis UT26
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DOI：
10.1128/jb.187.3.847-853.2005
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发表时间：
2005-02-01
影响因子：
3.2
通讯作者：
Nagata, Y
中科院分区：
文献类型：
--
作者：
Endo, R;Kamakura, M;Nagata, Y
少动鞘氨醇单胞菌UT 26利用γ-六氯环己烷（γ-HCH）作为唯一的碳和能量来源。在我们之前的研究中，我们克隆并鉴定了UT 26中通过氯氢醌（CHQ）将γ-HCH转化为马来酰乙酸酯（MA）的基因。在这项研究中，我们确定了一个MA还原酶基因，命名为linF，这是必不可少的γ-六氯环己烷在UT 26的利用。一个名为linEb的基因位于linF附近，其推导的产物与LinE具有显着的同一性（53%）。LinE是一种新型的开环双加氧酶，催化CHQ转化为MA。在大肠杆菌中表达的LinEb分别将CHQ和2，6-二氯氢醌转化为MA和2-氯马来酰乙酸。我们以前和现在的研究结果表明，UT 26（一）有两个基因簇，通过对苯二酚类中间体降解氯代芳香化合物，（二）至少利用两个基因簇的一部分来利用γ-六氯环己烷。
Sphingomonas paucimobilis UT26 utilizes gamma-hexachlorocyclohexane (gamma-HCH) as a sole source of carbon and energy. In our previous study, we cloned and characterized genes that are involved in the conversion of gamma-HCH to maleylacetate (MA) via chlorohydroquinone (CHQ) in UT26. In this study, we identified and characterized an MA reductase gene, designated linF, that is essential for the utilization of gamma-HCH in UT26. A gene named linEb, whose deduced product showed significant identity to LinE (53%), was located close to linF. LinE is a novel type of ring cleavage dioxygenase that catalyzes the conversion of CHQ to MA. LinEb expressed in Escherichia coli transformed CHQ and 2,6-dichlorohydroquinone to MA and 2-chloromaleylacetate, respectively. Our previous and present results indicate that UT26 (i) has two gene clusters for degradation of chlorinated aromatic compounds via hydroquinone-type intermediates and (ii) uses at least parts of both clusters for gamma-HCH utilization.