利用recA基因序列分析鉴定云南酵米面中伯克霍尔德菌属分离株

目的利用recA基因序列分析对云南省两起酵米面食物中毒案例中伯克霍尔德菌属病原菌进行分类鉴定。方法对基于16S rRNA序列分析鉴定为伯克霍尔德菌属的4株分离菌株和1株唐菖蒲伯克霍尔德菌标准株(CICC 10574),通过聚合酶链式反应(PCR)扩增recA基因片段、测序,将测序结果与GenBank中伯克霍尔德菌属中73个种的对应片段序列比对,并构建系统发育树。结果比较分析伯克霍尔德菌属中73个种的recA基因的亲缘关系,recA基因可以准确地区分鉴定伯克霍尔德菌属中包括食物中毒案例中4个分离株的不同的种,特别是在区分唐菖蒲伯克霍尔德种内不同致病亚种时有参考价值。结论 recA基因序列分析将酵米面食物中毒分离株鉴定为唐菖蒲伯克霍尔德菌,而且食物中毒案例中的4个分离株和植物病原菌及环境分离株的唐菖蒲伯克霍尔德菌的基因序列不同,具有独特的单核苷酸多态性(SNP),建议鉴定结果采用唐菖蒲伯克霍尔德菌椰毒致病变种(Burkholderia gladioli pv.cocovenenans)。

Identification of isolates in fermented corn flour food poisoning case in China by recA sequence analysis

Objective The four pathogens isolated from two outbreaks caused by fermented corn flour products in Yunnan Province were identified by recA partial sequence analysis. Methods The four isolates were already identified as Burkholderia spp. on the basis of 16S rRNA sequence analysis. They were amplified by recA specific primers in polymerase chain reaction together with Burkholderia gladioli (CICC 10574). The products were sequenced. The sequences were blasted with 73 species in Burkholderia genus and a phylogenetic tree was constructed. Results Comparative analysis of genetic relationship of recA gene could identify and classify the 73 species of Burkholderia, even subspecies of B.gladioli. Conclusion The four isolates from food poisoning cases could be identified as B.gladioli by recA sequence analysis. Their sequences were different from those of plant pathogens of B.gladioli with specific single nucleotide polymorphism(SNP), and was identified as Burkholderia gladioli pv.cocovenenans.