Polyethylene glycol modification ofCandida rugosa lipase

Abstract
Polyethylene glycol (PEG) was covalently attached to lipase (EC 3.1.1.3) fromCandida rugosa yielding a modified lipase of higher specific activity in hydrolytic and synthetic reactions in organic solvents. PEG of molecular weights 5000 and 1900 solubilized the lipase in selected organic solvents, but PEG of molecular weight 750 was too small to accomplish this completely. The modified lipase was 10 times more stable in water than native lipase, but was less stable in benzene. The selectivity of the modified lipase was also altered to favor reaction with oleic versus stearic acid.