Clark A G, Drake B
Biochem J. 1984 Jan 1;217(1):41-50. doi: 10.1042/bj2170041.
The glutathione S-transferases from the porina moth, Wiseanna cervinata, were purified by affinity chromatography, cation-exchange chromatography and preparative isoelectrofocusing. The major transferase (IV) was purified to homogeneity by a factor of 530-fold with a yield of 83%. Other transferases present were purified to a smaller degree (approx. 50-fold) to a stage of near-homogeneity. The transferases examined all had Mr values about 45 000-50 000. They appeared to be homodimers of either of two types of subunit, of Mr 22 800 and 24 600. Enzymes consisting of the different types of subunit were not immunologically cross-reactive. The major enzyme fractions separated by cation-exchange chromatography were both active with 1-chloro-2,4-dinitrobenzene, 1,2-dichloro-4-nitrobenzene, ethacrynic acid and iodomethane, but were inactive with 4-nitropyridine N-oxide, 1,2-epoxy-3-(p-nitrophenoxy)propane, bromosulphophthalein and p-nitrobenzyl chloride. The kinetics of the enzyme-catalysed reaction with enzyme IV were non-Michaelean with respect to both substrates. Both products were inhibitory. The results appear to be compatible with a random steady-state mechanism. It is concluded that these enzymes are very similar, in their physical and chemical constitution, in their catalytic properties and in their relationships with each other, to those enzymes that have been isolated from vertebrate organisms.
通过亲和色谱法、阳离子交换色谱法和制备性等电聚焦法对舞毒蛾（Wiseanna cervinata）的谷胱甘肽S-转移酶进行了纯化。主要的转移酶（IV）纯化至同质，纯化倍数为530倍，产率为83%。其他存在的转移酶纯化程度较低（约50倍），达到接近同质的阶段。所检测的转移酶的相对分子质量均约为45000 - 50000。它们似乎是由两种亚基组成的同二聚体，这两种亚基的相对分子质量分别为22800和24600。由不同类型亚基组成的酶在免疫上没有交叉反应。通过阳离子交换色谱法分离的主要酶组分对1-氯-2,4-二硝基苯、1,2-二氯-4-硝基苯、依他尼酸和碘甲烷均有活性，但对4-硝基吡啶N-氧化物、1,2-环氧-3-(对硝基苯氧基)丙烷、溴磺酞和对硝基苄基氯无活性。酶IV催化反应的动力学对于两种底物而言均不符合米氏方程。两种产物均有抑制作用。结果似乎与随机稳态机制相符。得出的结论是，这些酶在其物理和化学组成、催化特性以及它们之间的关系方面，与从脊椎动物中分离出的那些酶非常相似。
