Survey For Virulence Factors Of Enterococcus Strains And Prokaryotic Expression Of Enterococcus Faecalis Cytolysin CylLl,cylA

Objectives:The purpose of this study is to survey several virulence factors of entrococcus faecalis and prokaryotic expression of enterococcus faecalis cytolysin cylLl,cylA provide support to next study such as obtaining multiple clone antibodies in order to detect clinical infections caused by enterococcus faecalis and develop new therapy without antibiotics .Methods:According to the nucleotide sequence of pAD1 plasmid in Genebank(NO L37110),primers of cylL,cylA,gelE,efaA are designed and synthesized,then these four genes are detected by PCR among clinial enterococcus faecalis strains.Then cylLl ,cylA gene is cloned to pET42a vector amplyfied in top10 Ecoli strains,expressed in host strain BL21(DE3).The protein cylLl, cylA is detected by SDS-PAGE and Western Blot.Results:1.The positive incidences of cylA,cylL,gelE,efaA among clinical strains are 53.98%,52.21%,63.72%,64.60%. Incidences of virulence factors in Enterococcus faecalis were higher than Enterococcus faecium.2.cylLl,cylA recombinant fusion protein was successfully expressed in pet42a-BL21(DE3) system,detected in SDS-PAGE electrophoresis and Western Blot.Conclusions:Enterococcus faecalis is more virulent than Enterococcus faecium. Successful expression of cylLl,cylA fusion protein established the base to next study such as massive expression,purification as well as their biological function.