Change in substrate preference of Streptomyces aminopeptidase through modification of the environment around the substrate binding site.
We attempted to alter the substrate preference of aminopeptidase from Streptomyces septatus TH-2 (SSAP). Because Asp198 and Phe221 of SSAP are located in the substrate binding site, we screened 2,000 mutant enzymes with D198X/F221X mutations. By carrying out this examination, we obtained two enzymes; one specifically hydrolyzed an arginyl derivative, and the other specifically hydrolyzed a cystinyl derivative (65- and 12.5-fold higher k(cat) values for hydrolysis of p-nitroanilide derivatives than those of the wild type, respectively).
Arima
Jiro
J
Research Institute for Biological Sciences (RIBS), Okayama, 7549-1 Kibichuo-cho, Kaga-gun, Okayama 716-1241, Japan.
Uesugi
Yoshiko
Y
Iwabuchi
Masaki
M
Hatanaka
Tadashi
T
D000595:Amino Acid Sequence; D000626:Aminopeptidases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D001665:Binding Sites; D001709:Biotechnology / Q000379:methods; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009154:Mutation; D013302:Streptomyces / Q000201:enzymology* / Q000235:genetics; D013379:Substrate Specificity
D000626:Aminopeptidases