鸡蛋污染致病菌分离及鉴定

Isolation and identification of pathogenic bacteria from contaminated eggs

为了研究污染鸡蛋的致病菌,试验采用微生物分离纯化在鸡蛋表面得到4株菌,用形态学观察和生理生化初步判定为芽孢杆菌和葡萄球菌,再结合16Sr RNA分子方法对4株菌进行分类分析,先用PCR对目的菌进行基因扩增,经克隆及质粒测序,再登录NCBI中Gen Bank数据库进行相似性分析。结果表明:1号菌为蜡样芽孢杆菌Bacillus cereus GXBC-1,2号和3号菌为蜡样芽孢杆菌Bacillus cereus NC7401,4号菌为金黄色葡萄球菌Staphylococcus aureus。这些菌是食源性致病菌,致病性强,传染率高,对食品安全风险大。

To study the pathogenic bacteria contaminating eggs, used microbial purification and found 4 strains of bacteria were obtained from the surface of eggs using microbial isolation and purification techniques. The 4 strains of bacteria were initially judged as Bacillus and Staphylo- coccus using morphological observation with physiological and biochemical features. The 16Sr RNA molecular method was used and combined in the classification and analysis of the 4 strains of bacteria. The genes from target bacteria were amplified by PCR, and then were cloned and se- quenced. A similarity analysis was performed by logging on GenBank database in NCBI. The results showed that the strain 1 was identified as Bacillus cereus GXBC - 1, the strain 2 and 3 were identified as Bacillus cereus NC7401, and the strain 4 was identified as Staphylococcus au-reus. These bacteria were food - borne pathogenic bacteria that have strong pathogenicity and high transmission rate, which are big risks for food safety.