Dao M L, Watson J J, Delaney R, Johnson B C
J Biol Chem. 1979 Oct 10;254(19):9441-7.
A new form of cytoplasmic glucose-6-phosphate dehydrogenase (E.C.1.1.1.49) was purified from rat liver by protamine sulfate precipitation, ammonium sulfate fractionation, ion exchange chromatography with diethylaminoethyl cellulose, and affinity chromatography with Cibacron blue agarose and NADP agarose. This form of the enzyme has a specific activity of over 600 units/mg of protein and gives essentially a single band by polyacrylamide gel electrophoresis. The form of the enzyme isolated by this purification method is 3 times more active than the form purified from liver by previously reported procedures. The relative mass of this pure glucose-6-phosphate dehydrogenase enzyme was determined by disc gel electrophoresis to be 269,000. This high activity glucose-6-phosphate dehydrogenase enzyme, after inactivation by reaction with palmityl-CoA, was no longer precipitated by specific rabbit and goat antisera to this purified enzyme. Thus, the possibility still exists that starved fat-refed animals contain glucose-6-phosphate dehydrogenase (G6PD) enzyme protein in an inactivated form no longer detectable by either enzyme activity or immunoprecipitation.
通过硫酸鱼精蛋白沉淀、硫酸铵分级分离、用二乙氨基乙基纤维素进行离子交换色谱以及用汽巴克隆蓝琼脂糖和烟酰胺腺嘌呤二核苷酸磷酸（NADP）琼脂糖进行亲和色谱，从大鼠肝脏中纯化出一种新型的细胞质葡萄糖-6-磷酸脱氢酶（E.C.1.1.1.49）。这种形式的酶比活性超过600单位/毫克蛋白质，通过聚丙烯酰胺凝胶电泳基本上呈现单一条带。用这种纯化方法分离出的酶的活性是先前报道的从肝脏中纯化出的酶的3倍。通过圆盘凝胶电泳测定这种纯葡萄糖-6-磷酸脱氢酶的相对分子质量为269,000。这种高活性的葡萄糖-6-磷酸脱氢酶在与棕榈酰辅酶A反应失活后，不再被针对这种纯化酶的特异性兔和山羊抗血清沉淀。因此，饥饿后再喂食的动物仍有可能含有以失活形式存在的葡萄糖-6-磷酸脱氢酶（G6PD）酶蛋白，这种形式无论是通过酶活性还是免疫沉淀都无法再检测到。
