Antarctic, cold-adapted β-galactosidase of Pseudoalteromonas sp. 22b as an effective tool for alkyl galactopyranosides synthesis

The antarctic Pseudoalteromonas sp. 22b β-galactosidase was found to catalyze synthesis of alkyl galactopyranosides. The number of carbon atoms in C3–C6 alcohol molecules only slightly affected the yield of products. Reactions of transgalactosylation were conducted for 80 h and the maximum accumulation of their products was observed between 40 and 50 h. The highest and almost the same yields of alkyl galactosides were achieved at pH 6–9 and 10–30% water concentration. Like known mesophilic β-galactosidases, the antarctic enzyme more efficiently synthesized alkyl galactosides when reactions were carried out in mixtures of buffers and organic solvents (below 50%, v/v).