Evidence that both arginine 102 and arginine 747 are involved in substrate binding to neutral endopeptidase (EC 3.4.24.11)

摘要: Neutral endopeptidase (EC 3.4.24.11, NEP) is a Zn-metallopeptidase involved in the degradation of biologically active peptides, notably enkephalins and atrial natriuretic peptide. Recently, structure site this enzyme has been probed by site-directed mutagenesis, 4 amino acid residues have identified, namely 2 histidines (His583 His587), which act as zinc-binding ligands, glutamate (Glu584) catalysis, an arginine residue (Arg102), suggested to participate substrate binding. Site-directed mutagenesis now used investigate role other (Arg408, Arg409, Arg659, Arg747) that proposed possible further analyze Arg102. In each case, was replaced with methionine, both enzymatic activity IC50 values several NEP inhibitors were measured for mutated enzymes compared wild-type enzyme. The results suggest arginines, Arg102 Arg747, could be important inhibitor Arg747 seems positioned interact carbonyl amide group P'1 can modified when treated arginine-specific reagents phenylglyoxal butanedione. free carboxyl P'2 some substrates but not explain dual dipeptidylcarboxypeptidase nature NEP.