[A method of determining inhibitory constants during reversible inhibition of enzymatic hydrolysis of a substrate]. / Metod opredeleniia ingibitornykh konstant pri obratimom tormozhenii fermentativnogo gidroliza substrata.

ABSTRACT

Determination of inhibitory constants and antienzymic activity of reversible retardants of different type of action by the generalized inhibitory constant K sigma is estimated, results being presented. To determine more precisely the values of inhibitory constants of the competitive (Ki), noncompetitive (K'i) inhibition and of the generalized K sigma it is suggested to conduct linearization of the experimental data in coordinates 1/K sigma, s; 1/[S], where K sigma, s is a total inhibitory constant whose value depends on the substrate [S] concentration and to make calculations by the least-square method with the allowance for principal intervals of the Km values and the maximal rate of the enzymic reaction V. Comparative calculations are made by a computer using the BASIC/RT-60 language programme through the example of the acetyl choline acetyl hydrolase (EC 3.1.1.7) interaction with the quaternary phosphonium salts--reversible retardants of this enzyme.