Lowe S L, Reithel F J
J Biol Chem. 1975 Jan 10;250(1):94-9.
Bakers' yeast phosphoglucose isomerase was studied by both chemical and physical methods to determine its submit structure. Gel filtration in 6 M guanidine HCl as well as acrylamide gel electrophoresis of sodium dodecyl sulfatedentured phosphoglucose isomerase showed two speices corresponding to one-half and one-fourth of the preparative molecular weight of 119,400 determined by equilibrium centrifugation. Further centrifugation studies showed that the enzyme could be completely dissociated to species of 30,000 molecular weight. Peptide maps of tryptic hydrolysates of denatured and chemically modified enzyme showed that the protein is composed of four identical or nearly identical sub-units. The results of amino acid analysis, except half-cystine content, were compatible with identical subunits. The appearent partial specific volume and extinction coefficient were also determined.
通过化学和物理方法研究了面包酵母磷酸葡萄糖异构酶，以确定其亚基结构。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磷酸葡萄糖异构酶进行丙烯酰胺凝胶电泳，结果显示有两种组分，其分子量分别相当于通过平衡离心法测定的119,400制备分子量的二分之一和四分之一。进一步的离心研究表明，该酶可完全解离为分子量为30,000的组分。变性和化学修饰酶的胰蛋白酶水解产物的肽图表明，该蛋白质由四个相同或几乎相同的亚基组成。除半胱氨酸含量外，氨基酸分析结果与相同亚基相符。还测定了表观偏比容和消光系数。
