Christ-Hazelhof E, Nugteren D H, Van Dorp D A
Biochim Biophys Acta. 1976 Dec 20;450(3):450-61. doi: 10.1016/0005-2760(76)90018-7.
Serum albumins of certain animal species (cow, sheep, pig) accelerate the decomposition of prostaglandin endoperoxides, with formation of large amounts of prostaglandin D. The reaction is inhibited by arachidonic acid, which suggests an interaction of the endoperoxide with the fatty acid binding sites of serum albumin. Glutathione-S-transferases, in the presence of glutathione, convert the endoperoxide into a mixture of prostaglandin F2alpha, E2 and D2. The prostaglandin D/E-ratio depends on the transferase used. The known rat liver transferases give mainly prostaglandin F2alpha and E2, but a new transferase in sheep lung was discovered which gives rise to large quantities of prostaglandin F2alpha and D2. The sheep lung transferase was purified to homogeneity. Two iso-enzymes with identical enzymic activity were obtained. The major component (transferase SL 2, an iso-enzyme of glutathione-S-transferase, EC 2.5.1.18) has a molecular weight of 45 000 and consists of two subunits. Its isoelectric point is 9,8-9.9. These properties, as well as the amino acid composition and the substrate specificity for typical transferase substrates, indicate a close resemblance to transferase B (ligandin), a major binding protein of rat liver. Although purified glutathione peroxidase from erythrocytes is very active in catalysing the reduction of the 15-hydroperoxy group of prostaglandins, it does not have any effect on the decomposition of the endoperoxide group.
某些动物物种（牛、羊、猪）的血清白蛋白可加速前列腺素内过氧化物的分解，生成大量前列腺素D。该反应受花生四烯酸抑制，这表明内过氧化物与血清白蛋白的脂肪酸结合位点存在相互作用。谷胱甘肽-S-转移酶在谷胱甘肽存在的情况下，可将内过氧化物转化为前列腺素F2α、E2和D2的混合物。前列腺素D/E比值取决于所使用的转移酶。已知的大鼠肝脏转移酶主要生成前列腺素F2α和E2，但在绵羊肺中发现了一种新的转移酶，它可产生大量的前列腺素F2α和D2。绵羊肺转移酶被纯化至同质。获得了两种具有相同酶活性的同工酶。主要成分（转移酶SL 2，谷胱甘肽-S-转移酶的一种同工酶，EC 2.5.1.18）的分子量为45000，由两个亚基组成。其等电点为9.8-9.9。这些特性以及氨基酸组成和对典型转移酶底物的底物特异性，表明它与大鼠肝脏的主要结合蛋白转移酶B（配体结合蛋白）非常相似。尽管从红细胞中纯化的谷胱甘肽过氧化物酶在催化前列腺素15-氢过氧基的还原方面非常活跃，但它对过氧化物基团的分解没有任何影响。
