title: [pH-dependence of the esterolytic activity of terrylytine proteases].
abstract: The pH-dependences of the kinetic parameters of hydrolysis of alpha-N-henzoyl-L-arginine and N-benzoyl-L-tyrosine ethyl esters by terrylytine proteases I and II were studied. The experimental results proved evidence for the differences in the activities of these enzymes. The active center of protease I contains two groups with close pK values (6,5-7,0), one of which is presumably the imidazole group of histidine. The catalytic action of protease II is determined by the state of the ionizing groups with the ionization constants of about 6 and 8. The former functions in the deprotonated form, whereas the latter--in the protonated form.
mesh_terms: D000681:Amylases / Q000378:metabolism*; D001120:Arginine / Q000031:analogs & derivatives / Q000378:metabolism; D001230:Aspergillus / Q000201:enzymology*; D004338:Drug Combinations / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007527:Isoenzymes / Q000378:metabolism; D007700:Kinetics; D010447:Peptide Hydrolases / Q000378:metabolism*; D013379:Substrate Specificity; D014443:Tyrosine / Q000031:analogs & derivatives / Q000378:metabolism
chemical_list: D004338:Drug Combinations; D007527:Isoenzymes; C004464:N-benzoyl-L-arginine; C006716:benzoyltyrosine ethyl ester; C009402:amylase, phosphates, proteases drug combinations; D014443:Tyrosine; D001120:Arginine; D000681:Amylases; D010447:Peptide Hydrolases
vernacular_title: Zavisimost' esteroliticheskoĭ aktivnosti proteaz terrilitina ot pH.