Mechanism of phosphorylation of Ser residue catalyzed by cAMP-dependent protein kinase

概要

論文の詳細を見る
Quantum chemical calculations have been performed to clarify the function of the active catalytic subunit (C-subunit) of cAMP-dependent protein kinase (cAPK) that plays an important role in the regulation of blood glucose. It was found that the phosphorylation of Ser residue by cAPK proceeds via two elementary reactions; (i) an intermediate is formed from the enzyme-substrate complex (ES-complex), and (ii) the phosphorylated Ser is released from the active site. In the intermediate between the two elementary reactions, the Ser of the substrate is attached to the γ-phosphoric acid of the ATP, and the γ-phosphorus atom has a five-coordinated structure. The former elementary reaction is the rate-determining step, and the activation energy required for this phosphorylation reaction has been estimated to be 29.04kcal/mol. Hence, this phosphorylation reaction is expected to proceed at a body temperature of about 310K.
日本コンピュータ化学会の論文