Axelsson K, Eriksson S, Mannervik B
Biochemistry. 1978 Jul 25;17(15):2978-84. doi: 10.1021/bi00608a006.
An enzyme catalyzing thiol-disulfide interchange of glutathione and disulfides and the reaction between glutathione and thiosulfate esters has been purified 40 000-fold from rat liver cytosol. The enzyme, named thioltransferase (Askelöf, P., Axelsson, K., Eriksson, S., & Mannervik, B. (1974) FEBS Lett. 38, 263--267), was homogeneous in several electrophoretic systems, had an isoelectric point at pH 9.6, and contained 8.6% (w/w) carbohydrate. The catalytic activity had a distinct optimum at pH 7.5. A series of substrates was tested at a constant glutathione level; the kcat values (at 4mM glutathione) were all in the range of about 10(4) min-1. The substrates included mixed disulfides of glutathione, other low-molecular-weight disulfides, S-sulfocysteine and S-sulfoglutathione, and peptide disulfides such as insulin, oxytocin, ribonuclease, and the mixed disulfide of glutathione and egg-white lysozyme. The enzymatic reaction was inhibited by an excess of glutathione (greater than 4mM).
一种催化谷胱甘肽与二硫化物之间硫醇 - 二硫化物交换以及谷胱甘肽与硫代硫酸酯之间反应的酶已从大鼠肝细胞溶胶中纯化了40000倍。该酶名为硫醇转移酶（阿斯克洛芙，P.，阿克塞尔松，K.，埃里克松，S.，& 曼内维克，B.（1974年）《欧洲生物化学学会联合会快报》38卷，263 - 267页），在几种电泳系统中均为均一的，其等电点为pH 9.6，并且含有8.6%（重量/重量）的碳水化合物。催化活性在pH 7.5时有明显的最佳值。在谷胱甘肽水平恒定的情况下测试了一系列底物；kcat值（在4mM谷胱甘肽时）均在约10⁴ 分钟⁻¹ 的范围内。底物包括谷胱甘肽的混合二硫化物、其他低分子量二硫化物、S - 磺基半胱氨酸和S - 磺基谷胱甘肽，以及肽二硫化物，如胰岛素、催产素、核糖核酸酶，还有谷胱甘肽与蛋清溶菌酶的混合二硫化物。过量的谷胱甘肽（大于4mM）会抑制酶促反应。
