A lipase gene of Thermomyces lanuginosus: sequence analysis and high-efficiency expression in Pichia pastoris

Abstract

Lipase is a type of enzyme that decomposes and synthesizes triglyceride on hydrophilic and lipophilic interface, which plays an important role in lipid processing. A novel heat-resisting lipase gene (lip4) in Thermomyces lanuginosus was cloned to the expression vector pPICZαA and then transported into Pichia pastoris X33 for high-efficiency expression. The structure of this lipase (Lip4) was analyzed by multiple bioinformatics software. Results showed that the recombinant yeast cell concentration reached the peak at 144h and the lipase activity reached the maximum (3900U/mL) at 168h in the induction. S168, D223 and H280 form the triplet structure of the Lip4 and S168 is also involved in the pentapeptide structure of G166-H167-S168-L169-G170. Furthermore, S168 also constituted the active center of Lip4 with seven other conserved amino acids, such as G104/288, S105, A195, P196, V225, and I287. Specifically, the two α-helices of the lid structure outside the active pocket control the entry of the substrate. Therefore, the eukaryotic system was constructed to express Lip4 efficiently, and the amino acid sites related to the catalytic efficiency of the Lip4 were clarified, providing a theoretical basis for its subsequent property research and industrial application.