构建及鉴定表达胃泌酸调节素的乳酸乳球菌

目的:构建食品级表达胃泌酸调节素(oxyntomodulin,OXM)的乳酸乳球菌,鉴定其在体外?体内的表达水平?方法:构建重组质粒pNZ8149-OXM电转至乳酸乳球菌中,用Western blot检测重组乳酸乳球菌OXM表达水平?给小鼠喂食表达OXM的乳酸乳球菌后,用液质联用质谱检测小鼠血清OXM的含量?结果:重组质粒经测序鉴定正确,制备的重组乳酸乳球菌在nisin诱导5 h后OXM表达量最高,食用后小鼠血清OXM含量是对照组的2.5倍左右?结论:成功构建了表达胃泌酸调节素的乳酸乳球菌,为进一步探讨其减肥降脂效应提供了基础?

Construction and identification of recombinant Lactctococcus lactis expressing oxyntomodulin

Objective:To deliver oxyntomodulin (OXM) to the food-grade strains of Lactctococcus Lactis (L.lactis), and identify its expression level in vivo and in vitro. Methods: L.lactis was transformed with recombinant plasmid pNZ8149-OXM by electroporation, and oxyntomodulin expression was detected by Western blot. Then, pNZ8149-OXM-transformed L.lactis was administered orally to mice, and OXM were detected by HPLC-MS from serum samples. Results: The expression of recombinant OXM from the pNZ8149-OXM-transformed L.lactis reached a maximum at 5 h after induction with nisin. The level of OXM in the serum of mice fed with pNZ8149-OXM-transformed L.lactis was 2.5 times higher than that in the control group. Conclusion: The recombinant L.lactis expressing oxyntomodulin is successfully constructed and expressed. It provides the basis for further study on the effect of reducing weight and lipid.