弱化F1F0-ATPase植物乳杆菌的选育及产酸性能分析

摘要

Three mutant strains of Lactobacillus plantarum M04, M15 and M20 with reduced F1F0-ATPase activity were screened from acid production degeneration of Lactobacillus plantarum in MRS medium containing 500μg/mL neomycin sulfate. The characteristics of acid production results showed that the parent strain was better than three mutant strains of M04, M15 and M20. The ability of acid production of M20 declined significantly. The tolerance of acid results showed that the growth of mutant M20 was inhibited significantly in the pH 4.5 or pH5.5 of MRS liquid medium. The base sequence encoded β subunit of F1F0-ATPase of three mutant strains and original strain re-vealed that the site mutation have effect on the F1F0-ATPase activity. Among them, the F1F0-ATPase activity of mutant M20 changed greatly.%以植物乳杆菌为研究对象，利用硫酸新霉素筛选压力，筛选获得三株 F1F0-ATPase 活性弱化突变株 M04、M15和M20。产酸及耐酸性能分析表明：突变株M04、M15和M20的产酸性能均弱于出发株，其中M20的产酸性能明显下降；在pH5.5和4.5的MRS液体培养基中M20的生长明显受到抑制；编码F1F0-ATPase的β亚基碱基序列分析表明：三株突变株均发生碱基突变而弱化F1F0-ATPase活性，其中突变株M20在多个位点的碱基置换及缺失对菌株的F1F0-ATPase活性影响最大。