Nomura T, Fukui T, Ichikawa A
Department of Physiological Chemistry, Faculty of Pharmaceutical Sciences, Kyoto University, Japan.
Biochim Biophys Acta. 1991 Mar 8;1077(1):47-55. doi: 10.1016/0167-4838(91)90524-4.
Two types of nucleoside diphosphate kinase (NDP kinase I and NDP kinase II) have been purified from spinach leaves to electrophoretic homogeneity. The enzymes were copurified with apparent [35S]GTP-gamma S-binding activities. NDP kinase I, which was not adsorbed to a hydroxyapatite column, and NDP kinase II, which was adsorbed, had molecular weights of 16,000 and 18,000, respectively, as judged by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. The molecular weights determined by gel filtration were 92,000 and 110,000, respectively, suggesting that both enzymes are composed of six identical subunits. Minor differences in some amino acids between NDP kinase I and NDP kinase II were observed when both enzymes were analyzed for amino acid composition. The apparent [35S]GTP gamma S-binding activity of purified NDP kinase I and NDP kinase II was found to be due to the formation of a [35S]thiophosphorylated enzyme, which is the intermediate of the NDP kinase reaction.
已从菠菜叶中纯化出两种核苷二磷酸激酶（核苷二磷酸激酶I和核苷二磷酸激酶II），达到电泳纯。这两种酶与明显的[35S]GTP-γ-S结合活性一起被共纯化。不吸附于羟基磷灰石柱的核苷二磷酸激酶I和吸附的核苷二磷酸激酶II，在十二烷基硫酸钠存在下通过聚丙烯酰胺凝胶电泳判断，其分子量分别为16,000和18,000。通过凝胶过滤测定的分子量分别为92,000和110,000，表明这两种酶均由六个相同的亚基组成。当分析这两种酶的氨基酸组成时，观察到核苷二磷酸激酶I和核苷二磷酸激酶II之间某些氨基酸存在微小差异。发现纯化的核苷二磷酸激酶I和核苷二磷酸激酶II的明显[35S]GTPγ-S结合活性是由于形成了[35S]硫代磷酸化酶，它是核苷二磷酸激酶反应的中间体。
