Cloning and sequencing of a 2,5-dichloro-2,5-cyclohexadiene-1,4-diol dehydrogenase gene involved in the degradation of gamma-hexachlorocyclohexane in Pseudomonas paucimobilis
Cloning and sequencing of a 2,5-dichloro-2,5-cyclohexadiene-1,4-diol dehydrogenase gene involved in the degradation of gamma-hexachlorocyclohexane in Pseudomonas paucimobilis
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DOI：
10.1128/jb.176.11.3117-3125.1994
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发表时间：
1994-06
影响因子：
3.2
通讯作者：
Y. Nagata;R. Ohtomo;K. Miyauchi;M. Fukuda;K. Yano;M. Takagi
中科院分区：
文献类型：
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作者：
Y. Nagata;R. Ohtomo;K. Miyauchi;M. Fukuda;K. Yano;M. Takagi
在少动假单胞菌UT 26中，γ-六氯环己烷（γ-HCH）转化为2，5-二氯-2，5-环己二烯-1，4-二醇（2，5-DDOL），然后代谢为2，5-二氯氢醌。在此，我们从UT 26的基因组文库中分离了两个基因，它们在转化到恶臭假单胞菌和大肠杆菌中时表达2，5-DDOL脱氢酶活性。这两个基因产物的表观分子大小为28 kDa的十二烷基硫酸钠-聚丙烯酰胺凝胶电泳。第一个基因名为linC，与我们已经克隆的两个基因（linA和linB）分开，这两个基因是参与γ-HCH降解的基因。另一个命名为linX，位于编码γ-HCH脱氢酶的linA基因上游约1 kb处。分离出一种γ-六氯环己烷降解阴性突变体，命名为UT 72，它缺少完整的linC基因，但具有完整的linX基因。在质粒中给出的linC基因可以补充UT 72。这些结果有力地表明，linC基因而不是linX基因对于UT 26中γ-六氯环己烷的同化是必不可少的。推导的氨基酸序列的LinC和LinX显示的短链醇脱氢酶家族的成员的同源性。
In Pseudomonas paucimobilis UT26, gamma-hexachlorocyclohexane (gamma-HCH) is converted to 2,5-dichloro-2,5-cyclohexadiene-1,4-diol (2,5-DDOL), which is then metabolized to 2,5-dichlorohydroquinone. Here, we isolated from the genomic library of UT26 two genes which expressed 2,5-DDOL dehydrogenase activity when they were transformed into P. putida and Escherichia coli. Both gene products had an apparent molecular size of 28 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The first gene, named linC, located separately from the two genes (linA and linB) which we had already cloned as genes involved in the gamma-HCH degradation. The other, named linX, located about 1 kb upstream of the linA gene encoding gamma-HCH dehydrochlorinase. A gamma-HCH degradation-negative mutant, named UT72, which lacked the whole linC gene but had the intact linX gene was isolated. The linC gene given in a plasmid could complement UT72. These results strongly suggest that the linC gene but not the linX gene is essential for the assimilation of gamma-HCH in UT26. Deduced amino acid sequences of LinC and LinX show homology to those of members of the short-chain alcohol dehydrogenase family.