Purification, Crystallization and Some Properties of Lipase fromGeotrichum candidumLink

Abstract

Lipase (EC 3. 1. 1. 3) of Geotrichum candidum Link was purified by means of ammonium sulfate fractionation, DEAE-Sephadex column chromatography, gel-filtration on Sephadex G-100 and Sephadex G-200, and was finally crystallized in concentrated aqueous solution. It was confirmed that the crystallized preparation was homogeneous electrophoretically and ultracentrifugally. It was estimated with the crystalline enzyme that the sedimentation constant (s20, W) was 4.0, the isoelectric point was pH 4.33, and the molecular weight was 53, 000_??_55, 000. From the result of amino acid analysis, none of sulfur containing amino acid was detected in the enzyme. It was also recognized that the crystalline preparation contained about 7% of the carbohydrate and very small amount of lipid. It was characterized that the lipase was the most active at pH 5.6_??_7.0 on olive oil, at 40°C and was stable in the range of pH 4.2 to 9.8 at 30°C for 24 hr, and was stable below 55°C for 15min.