橡胶树内生沙雷氏菌脂肪酶基因SmLipase1的克隆和表达分析

脂肪酶在洗涤剂、食品、纸浆以及生物柴油等多个工业领域被广泛应用。不同的应用领域对脂肪酶的酶学特性有不同的要求,因此挖掘脂肪酶基因资源具有重要意义。本研究报道从橡胶树内生菌Serratiamarcescens ITBB5-1中克隆得到一个脂肪酶基因,命名为Sm Lipase1,编码662个氨基酸,pI 4.82,能分泌脂肪酶到培养基中。构建重组表达载体pET22b-Sm Lipase-1,转化大肠杆菌菌株BL21(DE3)。本研究表明该转基因菌株能高效表达脂肪酶,并在平板培养基上形成较大的透明圈,转基因菌株发酵培养所获得的培养液酶活性达到26 U/mL。此外,该酶还具有催化油脂与甲醇反应生产脂肪酸甲酯的活性,在生物柴油领域具有一定的开发价值。

Cloning and Expression Analysis of Lipase Gene SmLipase1 from the Endophyte Serratia Marcescens of Rubber Tree

Lipases are widely used in multiple industries such as detergent, food, paper pulp and biodiesel industry.Different application fields require different enzymatic properties of lipase, therefore, study on lipase gene resources is beneficiary to the industries. We cloned a lipase gene named as SmLipase1 from an endophytic bacterial strain ITBB5-1 from rubber tree. This gene encoded a total of 662 amino acids with pI of 4.82, which can secret lipase into the medium. Recombinant plasmid pET22 b-SmLipase-1 was constructed to transform Escherichia coli strain BL21(DE3). The study result indicated that the gene strain could high-effectively express lipase, and form a large transparent circle on the plate medium. The enzyme activity of the medium obtained by fermentation and culture of transgenic strains reached 26 U/mL. Besides, this enzyme could catalyze oil to react with methanol so as to produce fatty acid methyl ester, which has certain development value in the field of biodiesel.