细胞分裂素-铜（II）配合物的超氧化物歧化酶模拟活性。

Superoxide dismutase mimetic activity of cytokinin-copper(II) complexes.

作者信息

Inoue H, Hirobe M

出版信息

Biochem Biophys Res Commun. 1986 May 29;137(1):372-7. doi: 10.1016/0006-291x(86)91220-9.

Abstract

Dissociation constants of cytokinins, derivatives of purine which form complexes with cupric ion, were determined by spectrophotometry and the stability constants of their copper complexes by pH titration. The values found for kinetin were 3.76, 9.96, 7.8, and 15.3 for pK1, pK2, logk1, and log beta 2, respectively, and those for 6-benzylaminopurine were, in the same order, 3.90, 9.84, 8.3, and 15.9. The copper(II) complexes with kinetin and 6-benzylaminopurine had superoxide dismutase mimetic activity, and the reaction rate constants with superoxide, which were determined by polarography, were 2.3 X 10(-7) M-1 s-1 for kinetin and 1.5 X 10(-7) M-1 s-1 for 6-benzylaminopurine at pH 9.8 and 25 degrees C.

摘要

通过分光光度法测定了细胞分裂素（嘌呤衍生物，可与铜离子形成络合物）的解离常数，并通过pH滴定法测定了其铜络合物的稳定常数。激动素的pK1、pK2、logk1和logβ2的值分别为3.76、9.96、7.8和15.3，6-苄基腺嘌呤的相应值依次为3.90、9.84、8.3和15.9。激动素和6-苄基腺嘌呤的铜（II）络合物具有超氧化物歧化酶模拟活性，通过极谱法测定的它们与超氧化物的反应速率常数在pH 9.8和25℃时，激动素为2.3×10⁻⁷ M⁻¹ s⁻¹，6-苄基腺嘌呤为1.5×10⁻⁷ M⁻¹ s⁻¹。