Tamaki N, Hess B, Ikeda T, Kimura K, Hama T
Hoppe Seylers Z Physiol Chem. 1980 Jan;361(1):61-8. doi: 10.1515/bchm2.1980.361.1.61.
A mild procedure for the purification of glucosephosphate isomerase from baker's yeast (Saccharomyces cerevisiae) is reported. The purified enzyme was homogeneous and did not contain charge isomers as shown by polyacrylamide gel electrophoresis as well as DEAE-Sepharose column chromatography. Its molecular weight determined by gel filtration and sucrose density gradient centrifugation was approximately 120 000, which agreed with that of the enzyme in the crude extract as well as that of the renatured enzyme. Gel filtration in 6M guanidine/HCl as well as acrylamide gel electrophoresis of sodium dodecyl sulfate denatured glucosephosphate isomerase showed one single peak and gave a subunit molecular weight of 60 000. Cross-linking patterns obtained with yeast glucosephosphate isomerase after treatment with dimethyl suberimidate resulted in the appearance of dimers as the largest-linked product of the enzyme subunit. After dissociation the enzyme can readily be reassociated and renatured with a yield of maximum 73% and a pseudo first order rate constant of 0.12 min-1 at 25 degrees C.
报道了一种从面包酵母（酿酒酵母）中纯化葡萄糖磷酸异构酶的温和方法。纯化后的酶是均一的，聚丙烯酰胺凝胶电泳和DEAE-琼脂糖柱色谱显示其不含电荷异构体。通过凝胶过滤和蔗糖密度梯度离心测定其分子量约为120000，这与粗提物中的酶以及复性酶的分子量一致。在6M盐酸胍中进行凝胶过滤以及对十二烷基硫酸钠变性的葡萄糖磷酸异构酶进行丙烯酰胺凝胶电泳，均显示出一个单峰，且亚基分子量为60000。用亚胺基二琥珀酸二甲酯处理酵母葡萄糖磷酸异构酶后得到的交联模式显示，二聚体是该酶亚基最大的交联产物。解离后，该酶能够很容易地重新缔合和复性，在25℃时最大产率为73%，假一级速率常数为0.12 min⁻¹。
