两段牛乳铁蛋白肽基因在乳酸乳球菌中的共表达

Co-expression of two different bovine lactoferrin-peptides in Lactococcus lactis

根据乳酸乳球菌密码子的偏嗜性,优化设计并合成牛乳铁蛋白肽的两段基因序列LFcinB和LFampin,将其与乳酸乳球菌表达载体pAMJ399分别用SalⅠ和BglⅡ双酶切后进行连接,并电转化至乳酸乳球菌MG1363中,经酶切鉴定表明获得带有两段牛乳铁蛋白肽基因的重组乳酸乳球菌pAMJ399-LFcinBA/MG1363。结果表明,优化表达条件,在GM17培养基中添加3.8%的β-甘油磷酸二钠可以获得表达重组蛋白的适宜pH,West-ern-blot检测可见重组蛋白大小约13 ku,表明牛乳铁蛋白肽在重组乳酸乳球菌中获得了表达。

Based on the codon bias of Lactococcus lactis MG1363, both LFcinB and LFampin genes were optimized and then synthesized for protein expression. The cloned genes were inserted into L. lactis expression vector pAMJ399 digested by SalI and BglII, and then electro- transformed into L. lactis MG1363. The recombinant bacterium was verified by enzyme digestions, and named pAMJ399-LFcinBA/MG1363. The optimization for expression conditions showed that an addition of 3.8% β-glycerophosphate disodium salt hydrate into GM17 broth could create a proper pH environment for recombination protein expression. Western-blot analysis showed an expected band with 13ku. The results indicated that the recombinant bovine lactoferrin-peptides were successfully expressed in L. lactis.