title: Study on peptide hydrolysis by aminopeptidases from Streptomyces griseus, Streptomyces septatus and Aeromonas proteolytica.
abstract: We developed a spectrophotometric assay for peptide hydrolysis by aminopeptidases (APs). The assay enables the measurement of free amino acids liberated by AP-catalyzed peptide hydrolysis using 4-aminoantipyrine, phenol, peroxidase, and L-amino acid oxidase. We investigated the specificity of bacterial APs [enzymes from Streptomyces griseus (SGAP), Streptomyces septatus (SSAP), and Aeromonas proteolytica (AAP)] toward peptide substrates using this assay method. Although these enzymes most efficiently cleave leucyl derivatives among 20 aminoacyl derivatives, in peptide hydrolysis, the catalytic efficiencies of Phe-Phe hydrolysis by SGAP and SSAP exceed that of Leu-Phe hydrolysis. Furthermore, all enzymes showed the maximum catalytic efficiencies for Phe-Phe-Phe hydrolysis. These results indicate that the hydrolytic activities of bacterial APs are affected by the nature of the penultimate residue or flanking moiety and the length of the peptide substrate.
authors.affiliation: Research Institute for Biological Sciences (RIBS), Okayama, 7549-1 Kibichuo-cho, Kaga-gun, Okayama, 716-1241, Japan.
authors.forename: Jiro
authors.initials: J
authors.lastname: Arima
authors.forename: Yoshiko
authors.initials: Y
authors.lastname: Uesugi
authors.forename: Masaki
authors.initials: M
authors.lastname: Iwabuchi
authors.forename: Tadashi
authors.initials: T
authors.lastname: Hatanaka
mesh_terms: D000333:Aeromonas / Q000201:enzymology*; D000626:Aminopeptidases / Q000378:metabolism*; D006868:Hydrolysis; D007700:Kinetics; D010455:Peptides / Q000378:metabolism*; D012680:Sensitivity and Specificity; D013053:Spectrophotometry / Q000379:methods; D013302:Streptomyces / Q000201:enzymology*; D013379:Substrate Specificity
chemical_list: D010455:Peptides; D000626:Aminopeptidases