Dirr H W, Schabort J C
Department of Biochemistry, Rand Afrikaans University, Johannesburg, South Africa.
Biochem Int. 1987 Aug;15(2):381-4.
With 1-chloro-2,4-dinitrobenzene as the electrophilic substrate, the specific activity of glutathione S-transferase in rat haemolysates was found to range from 0.002 to 0.013 mumol/min/mg haemoglobin at 30 degrees C. To establish the glutathione S-transferase composition, chromatofocusing was used which indicated the presence of a single soluble isoenzyme with an apparent pI of 6.1. A molecular weight of 48,000 was determined for the enzyme by gel filtration. The transferase enzyme in intact erythrocytes is shown to catalyze the formation of S-(2,4-dinitrophenyl)-glutathione from 1-chloro-2,4-dinitrobenzene and endogenous glutathione. Efflux of this conjugate from erythrocytes proceeded at a rate of 13 nmol/min/ml at 37 degrees C.
以1-氯-2,4-二硝基苯作为亲电底物，发现在30℃时，大鼠溶血产物中谷胱甘肽S-转移酶的比活性范围为0.002至0.013μmol/分钟/毫克血红蛋白。为了确定谷胱甘肽S-转移酶的组成，采用了色谱聚焦法，结果表明存在一种单一的可溶性同工酶，其表观pI为6.1。通过凝胶过滤测定该酶的分子量为48,000。完整红细胞中的转移酶可催化1-氯-2,4-二硝基苯和内源性谷胱甘肽形成S-(2,4-二硝基苯基)-谷胱甘肽。在37℃时，这种共轭物从红细胞中的流出速率为13 nmol/分钟/毫升。
