Yanagisawa H
Biology Department, Aichi University of Education, Kariya, Japan.
Phytochemistry. 2001 Apr;56(7):643-7. doi: 10.1016/s0031-9422(00)00491-x.
Agmatine deiminase was purified to a specific activity of 537 nkat/mg protein using an improved procedure. The recovery was 47% and the enzyme was homogeneous and remarkably stable. The molecular mass of the enzyme as determined by gel filtration was 75 kDa, and SDS-PAGE suggests that the enzyme is a heterodimer composed of subunits of 43.5 and 44 kDa. The Km for agmatine was 12 microM and arcaine was shown to be a potent competitive inhibitor of the enzyme, with a Ki of 3.3 microM. The enzyme does not have either putrescine synthase activity or the activities of its components ornithine and putrescine transcarbamylase. These results distinctly demonstrate that agmatine deiminase is different from putrescine synthase.
采用改进的方法将胍丁胺脱亚氨酶纯化至比活性为537 nkat/mg蛋白质。回收率为47%，该酶均一且非常稳定。通过凝胶过滤测定该酶的分子量为75 kDa，SDS-PAGE表明该酶是由43.5 kDa和44 kDa亚基组成的异源二聚体。胍丁胺的Km为12 μM，肌肌肽被证明是该酶的有效竞争性抑制剂，Ki为3.3 μM。该酶既没有腐胺合酶活性，也没有其组分鸟氨酸和腐胺转氨甲酰酶的活性。这些结果清楚地表明胍丁胺脱亚氨酶与腐胺合酶不同。
