Analysis of the Phosphoryl Transfer Mechanism of c-AMP dependent Protein Kinase (PKA) by Penta-Coodinate Phosphoric Transition State Theory

Feng      Ni; Wu      Li; Yan-Mei      Li; Yu-Fen      Zhao

doi:10.2174/138920305774329296

Abstract

This review briefly covers recent literature of research on the phosphoryl transfer mechanism of PKA. Combining experimental and theoretical calculation results on enzymes with experimentally observed biomimic activities of phosphoryl amino acids and a small molecular model of catalytic core in PKA, a novel mechanism was proposed. The cooperative participation roles of both Asp166 and Lys168 via a penta-coodinate phosphoric intermediate was elucidated to conciliate the current different views of the phosphoryl transfer mechanism of PKA. Since many ATP-binding enzymes may share a similar phosphoryl transfer mechanism, this proposed mechanism might also apply to the mechanism of these enzymes, e.g., molecular motor and phosphatase among others.

Keywords: camp dependent protein kinase (pka), phosphoryl, amino acid, penta-coodinate, phosphoric intermediate, hexacoodinate phosphoric intermediate, phosphoryl transfer mechanism, lysine participation