关键词: 大肠杆菌, BTL2, 脂肪酶, 基因工程, 生物柴油

Abstract: For the high specific activity, thermo-stability and soluble expression of Bacillus thermocatenulatus lipase BTL2, this paper is focused on the fermentation of lipase BTL2 used for the enzymatic preparation of biodiesel as the main purpose, using E. coli expression system.Recombinant plasmid of BTL2 was constructed under the T7 promoter control after removal of its signal sequence and codon optimization.The voluminal activity of the codon-optimization recombinant strain improved significantly with respect to a control strain.Lipase activity of 12583 U·ml^-1(tributyrin)was obtained in the 5 L fermentor experiment in 15 hours (8 hours induction), with high-level lipase productivity of 839 U·ml^-1·h^-1.BTL2 produced by E.coli showed the capability for the preparation of biodiesel with methyl ester yield of 94.8% in 48 h.

Key words: E.coli, BTL2, lipase, genetic engineering, biodiesel