title: [Conformation aspects of peptide interaction with proteolytic enzymes. Alpha-chymotrypsin catalyzed hydrolysis of the cyclopeptides containing leucyltyrosyl fragments].
abstract: The studies were made on the interaction of alpha-chymotrypsin with a series of cyclopeptides cyclo(-L-leucyl-L-tyrosyl-glycyln-), n=4, 6 and 8 (I, II and III respectively), and cyclo(-L-leucyl-L-tryosyl-beta-aminovalero-yl2-) (IV). Compounds I and IV are resistant to enzyme action whereas cyclopeptides II and III proved to be the substrates, their kinetic constants being Km=15.4 and 13.2 mM and kcat=0.54 and 9.53 sec-1 respectively. The binding capacity of cyclopeptides I-IV is evaluated by their competitive inhibition of alpha-chymotrypsin catalyzed hydrolysis of N-acetyl-L-tyrosine methyl ester.
mesh_terms: D002918:Chymotrypsin / Q000378:metabolism*; D007700:Kinetics; D007930:Leucine; D009842:Oligopeptides; D010456:Peptides, Cyclic; D014443:Tyrosine
chemical_list: D009842:Oligopeptides; D010456:Peptides, Cyclic; D014443:Tyrosine; D002918:Chymotrypsin; D007930:Leucine