Application of site-directed lipase mutants on regioselective acylation of monosaccharides

Mutants F344V and F345V of Candida rugosa lipase1 (CRL1) were tested in acylation reactions of monosaccharide derivatives 1-8, in order to study the regioselectivity, and the substrate specificity of lipase variants towards unnatural substrates, such as carbohydrates. Mutant F344V showed a better reaction kinetics and/or regioselectivity then the wild type enzyme with several substrates while mutant F345V was inefficient in most cases. With the aim of correlating experimental data with the structural features of the enzyme and substrates, the interaction of substrates methyl 4,6-O-benzylidene-alpha-D-glucopyranoside (5a) and 4,6-O-benzylidene-alpha-D-galactopyranoside (6a) with the wild type enzyme and the mutant F344V was investigated, using a molecular modelling approach