Hydrolysis of 4-Nitrophenyl Phosphate by (Amino Acidato)zinc Complexes

Abstract

Simple zinc complexes of glycine, histidine, and cysteine are proposed as evolutionary models for hydrolytic enzymes. Catalytic activity of (amino acidato)zinc complexes has been studied towards hydrolysis of 4-nitrophenyl phosphate at 40 °C over the pH range 5.0—10.0 by monitoring release of p-nitrophenol at 405 nm. Detailed kinetic investigations on hydrolysis of ester catalyzed by zinc complexes are discussed through formation of (amino acidato)zinc-substrate complex. Mechanistic and evolutionary aspect of this study are discussed in relation to the esterase property of the zinc metalloenzymes.