CHARACTERISTICS OF CYSTEINESULFINATE-FORMING ENZYME SYSTEM IN RAT LIVER
CHARACTERISTICS OF CYSTEINESULFINATE-FORMING ENZYME SYSTEM IN RAT LIVER
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DOI：
10.1016/0926-6593(66)90176-7
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发表时间：
1966-01-01
期刊：
影响因子：
--
通讯作者：
SORBO, B
中科院分区：
文献类型：
--
作者：
EWETZ, L;SORBO, B
研究了在羟胺存在下，大鼠肝脏制剂氧化半胱氨酸为半胱氨酸亚硫酸盐的反应。将该化合物添加到检测系统中，以抑制反应产物的酶破坏。报道了该酶体系的最佳测定条件。该反应由可溶部分中的一种热不稳定因子催化，并受到TPNH、亚铁离子和线粒体或微粒体的刺激。颗粒组分中的刺激活性是热不稳定的。该酶系似乎是L-半胱氨酸所特有的，因为当以D-半胱氨酸、L-半胱氨酸、谷胱甘肽或半胱胺为底物时，几乎没有检测到亚硫酸盐的形成。在所研究的不同大鼠组织中，只有肝脏具有显著的活性。该酶体系可被重金属试剂(EDTA、氰化物、邻菲罗啉)、巯基试剂对羟基苯甲酸汞和碘乙酸酯抑制，但不受亚砷酸盐的抑制。
The oxidation of cysteine to cysteinesulfinate by rat-liver preparations in the presence of hydroxylamine has been studied. This compound is added to the assay system in order to inhibit the enzymatic destruction of the reaction product. The optimum assay conditions for the enzyme system are reported. The reaction is catalysed by a heat-labile factor found in the soluble fraction and is stimulated by TPNH, ferrous ions and mitochondria or microsomes. The stimulating activity in the particulate fractions is heat-labile. The enzyme system appears to be specific for L-cystein, as very little sulfinate formation was detected when D-cysteine, L-cystine, glutathione or cysteamine was used as substrate. Among different rat tissues studied, only liver contained significant activity. The enzyme system is inhibited by heavy-metal reagents (EDTA, cyanide, o-phenanthroline) and by the sulfhydryl reagent p-hydroxymercuribenzoate and iodo-acetate, but not by arsenite.