Effect of Chemical Modification of a Histidine and a Lysine Residue of Pea Seed Nucleoside Diphosphate Kinase

Abstract

Chemical modification of a histidine and lysine residue inactivates pea seed nucleoside diphosphate kinase (NDP kinase). Thus there seems to be a reactive lysine residue, at the active site of pea seed NDP kinase, in addition to the histidine residue phosphorylated by the substrate ATP as a consequence of the enzyme reaction. The presence of a reactive lysine at the active site of the enzyme could explain why a small amount of N-ε-phospholysine, as well as 1-phosphohistidine and 3-phosphohistidine, is formed on alkaline hydrolysis of the enzyme.