在耶尔森氏菌强毒力岛(HPI)的基因中,fyuA编码鼠疫菌素受体与细菌的摄铁能力调节有关,int编码的整合酶与HPI在大肠杆菌基因组asn-tRNA位点的整合相关。根据GenBank中已发表的HPI基因序列设计2对引物,分别用于fyuA和int的PCR扩增。将从3株仔猪腹泻源HPI+大肠杆菌(S70903株、S70925株、S70931株)中扩增的片段克隆至pGEM-Teasy载体,分别获得含有fyuA和int的重组质粒。琼脂糖凝胶电泳、序列测定及分析表明:所克隆的fyuA基因大小均为948 bp,与已发表序列的同源性为98.6%~100%。所克隆的int基因片段大小均为1 391 bp,与已发表序列的同源性为96.0%~99.6%。研究结果提示,这3株细菌的fyuA基因并没有因为HPI的转移而缺失或被修饰,并且均整合在大肠杆菌基因组asn-tRNA位点。
The Escherichia coli isolates which harbored the high pathogenicity island(HPI) are more frequently associated with porcine diarrhea.Among the HPI-located genes,fyuA is specific for the pesticin receptor and the integrase gene,int,is associated with the insertion to the chromosomal asn-tRNA genes of HPI.In this research,2 sets of primers were designed and synthesized to amplify the fyuA and the int genes according to the reference sequences published in the GenBank.The PCR products of fyuA and int genes fro...