Heterologous Expression and Biochemical Characterization of Lipase from Burkholderia cepacia LulO-1

摘要

Even though lipase genes from a variety of microorganism have been cloned and over-expressed, the prospective lipase resources for commercial production and industry application are still limited. In the present study, a lipase from Burkholderia cepacia LulO-1 is heterologously over-expressed in Escherichia coli strain BL21(DE3) and purified to homogeneity. The molecular weight of the recombinant lipase from B. cepacia LulO-1 (abbreviated as lipase Lu 10-1) is estimated to be about 33 kDa by SDS-PAGE. The lipase LulO-1 has a priority for the long- chain length substrates. The optimal temperature of lipase LulO-1 is 60°C and it preserves high thermostability with residual activities of over 80% after 100 h at 60°C or over 60% after 30 h at 70°C. The optimal pH of lipase Lul0-1 is 9.0 and it has broad pH adaptability over a range of 5.0-10.0 retaining 80% activity between pH 6.0 and 9.0 after incubation at 37°C for 24 h. Moreover, the enzymatic activity of lipase Lul0-1 is not obviously affectedby several metal ions and it exhibites solid tolerance and stability towards various surfactants and organic solvents. The present study provides the basis for the potential applications of lipase Lul0-1 in related industries.