MULTICOMPETITIVE ENZYMATIC-REACTIONS IN ORGANIC MEDIA - APPLICATION TO THE DETERMINATION OF LIPASE ALCOHOL SPECIFICITY

Multicompetitive reactions catalyzed by lipases in organic media were used for the determination of lipase specificity towards alcohols. The competitive factors (alpha, defined as the ratio of the kinetic powers, k(cat)/K(m), for two substrates in competition for the enzyme active site) were estimated in a one-step experiment and a scale of specificity was easily deduced. The specificity towards the alcohol chain length and degree of substitution of seventeen commercial lipase preparations was investigated. The results show that, like fatty acids, alcohols greatly influence the reaction rates of lipase catalyzed reactions in organic solvents. Five groups of alcohol specificity are proposed after using the statistical method of principal component analysis.