Characterization of Genetic Structures of the QepA3 Gene in Clinical Isolates of Enterobacteriaceae

Frontiers in Microbiology

Yonghua eMou¹  Jiayu eChen¹  Dongguo eWang²  Liqin eYang³  Haijun eLI³  Xitian eHuang⁴ 

[1] Medical College of Taizhou University and the Institute of Molecular Diagnostics of Taizhou University;Taizhou Municipal Hospital, affiliated with Medical College of Taizhou University and the Institute of Molecular Diagnostics of Taizhou University;Taizhou Municipal Hospital, affiliated with Medical College of Taizhou University;Wenling Hospital, affiliated with Wenzhou Medical University;

关键词: Genetic structure;    Gene variation;    Plasmid-mediated quinolone resistance;    Recombinant plasmid;    QepA3 gene;   

DOI  :  10.3389/fmicb.2015.01147

来源: DOAJ

【 摘 要 】

QepA is one of the genes that confer quinolone resistance in bacteria. The aim of this study was to analyze the genetic structures of plasmids that carry a qepA3, a recently discovered allele of qepA in Enterobacteriaceae clinical isolates. 656 non-redundant Enterobacteriaceae clinical isolates were screened for the qepA3 gene and five isolated were identified to carry the gene. Plasmids were isolated from these isolates and were found to increase antibiotic resistance once the plasmids were transferred to Escherichia coli. These plasmids were subcloned and sequenced to analyze the genetic structures surrounding the the qepA3 gene. The results showed that the five plasmids had different genetic structures; one of qepA3-containning isolates had either the blaCTX-M-14 or blaTEM-12 gene in place of the blaTEM-1 gene. The structures of both pKP3764 and pECL3786 have not been previously described. In comparison with pHPA, there were a number of changes in DNA sequences up- and down-stream the qepA3 gene. These findings provide better understanding of the genetic variations in qepA3 and would be useful for diagnosis and control of quinolone resistance in clinical settings.

【 授权许可】

Unknown