PURIFICATION AND CHARACTERIZATION OF A LIPASE FROM CANDIDA LIPOLYTICA
Zhang Jinhong, Liu Zhenyu *, Liu Huijun *, Liu Jing ** , Yu Yaoting (Institute for Molecular Biology, Bioactive Materials Research Laboratory, Nankai, University, Tianjin, 300071) Duan Jiangyan (Department of Biology, Shanxi Normal University, Li
Commerical lipase of Candida lipolytica was purified to homogeneity by a single chromatography on phenyl sepharose. The hydrophobic interaction chromatography conditions were designed and optimized. The activity of the enzyme was measured before and after purification; molecular weight and isoelectric point of purified enzyme were determined. Experimental results showed that:① With phenyl sepharose as a partitioner phase, the mixed solvent system of peperazine and 2 propanol as a mobile phase, the homogenous lipase was obtained directly from crude lipase of Candida lipolytica . ② By purificaiton, the specific activity of lipase could be raised 12 13 folds. ③This protein had a molecular weight of 20.8Kda as analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis. ④Isoelectric focusing in Coomassie Brilliant Blue R staining revealed a single protein band. The protein band is situated between the bands of 3.5 and 4.55, just below the band of 4.55; therefore the isoelectric point of the protein is about pH 4.50.