title: Competitive inhibition by the D-isomer in racemic mixtures used as substrate in kinetic studies: a simple method for data treatment.
abstract: A set of equations was applied that allows the use of racemic mixtures for the estimation of kinetic parameters in systems where the L-isomer is substrate and the D-isomer a competitive inhibitor, displaying data as double reciprocal plots. A statistical treatment was introduced that renders compatible the output of presently available programs with the specific model requirements, with few additional calculations. An example is shown with beta-trypsin and its inhibition of benzozyl-D-arginine p-nitroanilide (Ki = 1.12 mM, pH 8,0, 37 degrees C).
mesh_terms: D001586:Benzoylarginine Nitroanilide / Q000494:pharmacology; D001667:Binding, Competitive; D003201:Computers; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D007700:Kinetics; D013223:Statistics as Topic; D013237:Stereoisomerism; D013329:Structure-Activity Relationship; D013379:Substrate Specificity; D014361:Trypsin Inhibitors / Q000494:pharmacology
chemical_list: D004791:Enzyme Inhibitors; D014361:Trypsin Inhibitors; D001586:Benzoylarginine Nitroanilide