Killilea S D, Whelan W J
Biochemistry. 1976 Mar 23;15(6):1349-56. doi: 10.1021/bi00651a028.
Glycogen synthase b was purified from rabbit liver by a procedure involving isolation of the glycogen-enzyme complex, DEAE-cellulose chromatography, and affinity chromatography. The purified enzyme had a specific activity of 25 mumol of glucose transferred from UDPglucose into glycogen per min per mg of protein at 30 degrees C in the presence of 10 mM glucose 6-P, and appeared to be homogeneous by the criterion of polyacrylamide disc gel electrophoresis. The b form was convertible into the a form by a rabbit-liver protein phosphatase. A subunit size of 85 000 was determined by electrophoresis in sodium dodecyl sulfate and molecular weights of 183 000 +/- 20 000 and 170 000 +/- 21 000 were determined for the a and b forms of the enzyme, respectively. On conversion of the a into the b form, 1.13 mol of phosphate was incorporated per 85 000 g of protein. The degree of phosphorylation and loss of glycogen synthase a activity paralleled each other.
糖原合酶b是通过一种包括糖原 - 酶复合物分离、DEAE - 纤维素色谱和亲和色谱的方法从兔肝中纯化得到的。在10 mM葡萄糖6 - 磷酸存在下，30℃时，纯化后的酶每毫克蛋白质每分钟有25 μmol葡萄糖从UDP葡萄糖转移到糖原中，根据聚丙烯酰胺圆盘凝胶电泳标准，该酶似乎是均一的。b型可被兔肝蛋白磷酸酶转化为a型。通过十二烷基硫酸钠电泳测定亚基大小为85000，该酶的a型和b型分子量分别测定为183000±20000和170000±21000。从a型转化为b型时，每85000 g蛋白质掺入1.13 mol磷酸。磷酸化程度与糖原合酶a活性丧失相互平行。
