INFLUENCE OF THE HYDROPHOBICITY OF LIPASE ISOENZYMES FROM CANDIDA-RUGOSA ON ITS HYDROLYTIC ACTIVITY IN REVERSE MICELLES

Two isoenzymes of Candida rugosa lipase, having the same mol.wt., size and similar aminoacid sequence, mere studied in reverse micelles of A OT. The results demonstrated the relevance of lipase hydrophobicity in reactions in anionic micelles, This is a key factor in mitigating the inhibition effect of charged micelles, The more hydrophobic isolipase A was a better biocatalyst for hydrolytic processes in these systems, Its alpha-helix content increased from 31% to 49% of the total struct ure in reverse micelles. A fluorescence study indicated a more apolar environment for the more hydrophobic isolipase A. Emission spectra of this isolipase in the AOT systems were blue shifted, At omega(0) value s where each isolipase presented its maximum activity, a decrease of t he emission intensity of Trp was found. An enzyme and substrate depend ence of optimal omega(0) is reported, The different interaction of iso lipases A and B with the micellar system produced an opposite omega(0) dependence to their stabilities. The more hydrophobic lipase A had hi gher stability at higher droplet sizes.