广东省食物中毒暴发疫情中沙门菌和金黄色葡萄球菌自动化核糖体基因分型研究

Automated ribotyping of Salmonella and Staphylococcus aureus in food poisoning of Guangdong province

目的为了解广东省常见食源性致病菌沙门菌和金黄色葡萄球菌（金葡菌）的遗传物质多态性特征，探索其鉴定及溯源方法。方法运用自动化核糖体基因分型系统，用EcoRI酶或PvuⅡ酶，对广东省分离的沙门菌和金葡菌进行分子分型研究。应用Bio Numerics软件比对不同来源、时间和地点的分离株，分析菌株间的相关陆。结果使用PvuⅡ酶对32株沙门菌酶切，分为19个核糖体型，使用EcoRI酶对14株沙门菌酶切，分为2个核糖体型。使用EcoRI酶对49株金葡菌酶切，分为31个核糖体型，表现出较大的遗传多样性。结论自动化核糖体基因分型能有效鉴定沙门菌和金葡菌。沙门菌血清分型与Ribotyping分型无高度相关性，但两者结合，能更有效鉴定菌株间的亲缘关系，确定食物中毒的来源和传染途径。

Objective To understand the genetic polymorphism of Salmonella and Staphylococcus aureus in Guangdong province, as well as to explore methods for identifying and tracing the source of these two foodborne pathogens. Methods Using the automated ribotyping system, two foodborne pathogens were tested with either EcoR I or Pvu II restriction enzymes. BioNumerics software was then applied for image analysis, database establishment and other corresponding analysis. Results Digestion of 32 Salmonella isolates with Pvu II yielded 19 different ribotypes, and digestion of 14 Salmonella isolates with EcoR I yielded 2 different ribotypes. Staphyloccus aureus isolates showed greater genetic diversity, whereas EcoR I digestion of 49 different isolates yielded 31 different ribotypes. Conclusion Unique Salmonella and Staphylococcus aureus isolates could be identified through ribotyping. Although Salmonella serotyping and ribotyping were not strongly correlated, the combination of both restriction enzymes could be used to more effectively identify the genetic relationship among different strains as well as the source of food poisoning. Thus, not only could the genetic relationships amongst the different strains be inferred through ribotyping skills, the source of food poisoning and mode of transmission could also be determined under the use of this method.