EVIDENCE THAT DDT-DEHYDROCHLORINASE FROM THE HOUSEFLY IS A GLUTATHIONE S-TRANSFERASE
EVIDENCE THAT DDT-DEHYDROCHLORINASE FROM THE HOUSEFLY IS A GLUTATHIONE S-TRANSFERASE
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DOI：
10.1016/0048-3575(84)90018-x
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发表时间：
1984-01-01
影响因子：
4.7
通讯作者：
SHAMAAN, NA
中科院分区：
文献类型：
--
作者：
CLARK, AG;SHAMAAN, NA
通过涉及亲和层析、凝胶渗透层析和制备型等电聚焦的程序，以高度纯化的形式分离出DDT脱盐酸酶。至少有两种蛋白质似乎具有 DDT 脱盐酸酶活性；其中主要的一个被纯化了 660 倍。这似乎是二聚体，亚基的分子量为 23,000 和 25,000。另一种具有这种活性的蛋白质似乎由 2 个相同的 MW 25,000 亚基组成。具有最大活性的蛋白质在 pH 7.1 时呈等电点。在十二烷基硫酸钠存在和不存在的情况下，在分析凝胶电泳上它是均匀的。相同的蛋白质在聚丙烯酰胺凝胶中的分析电聚焦中产生了许多次要蛋白质条带，但有证据表明这些条带可能是人为的。两种纯化形式的酶均对 CDNB [十二烷基硫酸钠] 和 DCNB [3, 4-二氯硝基苯] 具有显着的谷胱甘肽 S-转移酶活性。一种酸性蛋白，分子量为 23,000 的亚基二聚体，以 CDNB 为底物具有显着的 GSH 转移酶活性，但没有 DDT 脱盐酸酶活性。
DDT dehydrochlorinase was isolated in a highly purified form by a procedure involving affinity chromatography, gel-permeation chromatography and preparative isoelectrofocusing. At least two protein species appeared to possess DDT dehydrochlorinase activity; the principal one of these was purified by a factor of 660-fold. This appeared to be dimeric with subunits of MW of 23,000 and 25,000. Another protein with this activity appeared to consist of 2 identical subunits of MW 25,000. The protein with greatest activity was isoelectric at pH 7.1. It was homogeneous on analytical gel electrophoresis in both the presence and absence of sodium dodecylsulfate. The same protein generated a number of minor protein bands on analytical electrofocusing in polyacrylamide gels, but there is evidence that these bands may be artifactual. Both purified forms of the enzyme possessed substantial glutathione S-transferase activity with both CDNB [sodium dodecylsulfate] and DCNB [3, 4-dichloronitrobenzene]. An acidic protein, a dimer of subunits of MW 23,000 had substantial GSH transferase activity with CDNB as substrate, but had no DDT dehydrochlorinase activity.