大肠杆菌O157:H7 rfbE基因和fliC基因的克隆与序列分析

根据已发表的E．coli O157：H7 EDL933株的rfbE基因和fliC基因，设计了两对引物，分别对两个O157：H7，菌株的rfbE基因和一个菌株的fliC基因进行PCR，并将PCR产物克隆于pMD18-T栽体质粒。测序结果表明，获得到了与理论相符的582bp rfbE基因片段和802bp fliC基因片段。一株菌的rfbE基因存在无意义突变（两个）。而另一株菌fliC基因有一个有意义突变（aac→gac）

Cloning and Sequencing of rfbE gene and fliC gene in E.coli O157:H7

To clone and analysize rfbE and fliC genes of E.coli O_(157):H_7 , two primers were designed according to the sequence of rfbE gene and fliC gene of E.coli O_(157):H_7 EDL933 strain.The part fragment of rfbE gene of two E.coli O_(157):H_7 ,882364 and 021210 strain, were amplified by polymerase chain reaction(PCR) respectively. Both PCR products were cloned into pMD-18 vector and identified by BamH I ,HindIII and EcoRI and two positive recombinants containing rfbE gene wer e selected and sequenced.With the same method another positive recombinant conta ining fliC gene from 021210 strain was analysized. The result suggested homology of the rfbE gene between 882364 and 021210 strain was 99% for nucleotide seque nce .While the homology of the fliC gene compared with GENBANK sequence (AF22848 7)was 99%.