title: Fairly marked enantioselectivity for the hydrolysis of amino acid esters by chemically modified enzymes.
abstract: The hydrolysis (deacylation) of enantiomeric substrates by the chemically modified enzymes decanoyl-alpha-chymotrypsin and decanoyl-trypsin was studied. Reaction activity for decanoyl-alpha-chymotrypsin was lower than that for the native enzyme, although intriguingly the enantioselectivity was markedly enhanced as compared with the native enzyme. In particular, the apparently complete enantioselective catalysis was attained for the hydrolytic cleavage of p-nitrophenyl N-dodecanoyl-D(L)-phenylalaninates. The enhancement of enantioselectivity, however, was not observed for decanoyl-trypsin. These results suggest that the chemically modified alpha-chymotrypsin by addition of hydrophobic groups has promoted enantioselectivity for the hydrolysis of hydrophobic esters.
authors.affiliation: Division of Applied Chemistry, Graduate School of Sojo University, 4-22-1 Ikeda, Kumamoto 860-0082, Japan.
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Yano
authors.forename: Kenji
authors.initials: K
authors.lastname: Shimada
authors.forename: Jiro
authors.initials: J
authors.lastname: Okai
authors.forename: Koichi
authors.initials: K
authors.lastname: Goto
authors.forename: Yoko
authors.initials: Y
authors.lastname: Matsumoto
authors.forename: Ryuichi
authors.initials: R
authors.lastname: Ueoka
mesh_terms: D000465:Algorithms; D000596:Amino Acids / Q000737:chemistry / Q000378:metabolism*; D002384:Catalysis; D002918:Chymotrypsin / Q000737:chemistry / Q000378:metabolism*; D004952:Esters / Q000737:chemistry / Q000378:metabolism; D006868:Hydrolysis; D007700:Kinetics; D013237:Stereoisomerism; D013329:Structure-Activity Relationship; D014357:Trypsin / Q000737:chemistry / Q000378:metabolism*
chemical_list: D000596:Amino Acids; D004952:Esters; D002918:Chymotrypsin; D014357:Trypsin