Resolution of Ca2+—calmodulin‐activated protein kinase from wheat germ

[摘要]

A soluble Ca²⁺- and Ca²⁺—calmodulin-activated protein kinase was partially purified from wheat germ. The phosphorylation of histones and casein catalyzed by this enzyme is largely Ca²⁺-dependent. After repeated gel filtration of the protein kinase in the presence of 1 mM EGTA, the phosphorylation of casein and histones by the enzyme is activated 3-fold and up to 16-fold, respectively, by added calmodulin (12.5 μM). Such activation of the protein kinase by calmodulin is Ca²⁺-dependent. The protein kinase binds to calmodulin—Sepharose 4B in a Ca²⁺-dependent fashion. This type of Ca²⁺-activated protein kinase may be involved in stimulus—response coupling in plants.

[学科分类] 生物化学/生物物理

[关键词] Calmodulin;Protein kinase;Wheat germ;Histone;Calcium;Phenothiazine;cyclic AMP;adenosine 3′;5′-monophosphate;CAPP;2-chloro-10-(3-aminopropyl) phenothiazine