16S rDNA序列分析鉴定一株合浦珠母贝共附生乳酸菌

摘要

从合浦珠母贝(Pinctada fucata)粘液中分离纯化得到一株抗菌物质产生菌F9,利用16S rDNA方法鉴定该菌株为棒状乳杆菌(Lactobacillus coryniformis).通过琼脂扩散法测定了该菌的抑菌谱,发现该菌发酵液上清液在排除有机酸和过氧化氢(H2O2)的影响后仍对金黄色葡萄球菌(Staphyloccocus aureus)等多种食源性致病菌有明显的抑菌作用.对该菌发酵液抑菌物质进行超滤分析及蛋白酶处理,可推断该抗菌物质为分子量在5～10 kDa的蛋白类物质.%The strain F9 , which can produce antibacterial substances, was isolated from the Pinctada fucata mucus and finally identified as Lactobacillus coryniformis by 16S rDNA sequence analysis. The antimicrobial spectrum of strain F9 was investigated with agar diffusion method. The results show that the antimicrobial activity of the supernatant is not due to the existence of hydrogen peroxide and organic acid in the solution, and can significantly inhibit various common foodborne pathogens such as Staphyloccocus aureus. It is inferred that the antibacterial substances are proteins with molecular weight of 5 ～ 10 kDa based on ultrafiltration analysis and protease hydrolysis.