Molecular Typing of Staphylococcus Aureus, the Clone and Expression of Panton-Valentine Leukocidin Gene
|School||PLA Postgraduate Medical School|
|Course||Clinical Laboratory Science|
|Keywords||Bloodstream infections Staphylococcus aureus Molecular typing Panton-Valentine leukocidin Clone Expression|
Objective: To understand our hospital induced molecular epidemiological characteristics of bloodstream infections Staphylococcus aureus; screening bloodstream infections Staphylococcus aureus Panton-Valentine leukocidin gene (pvl gene) to carry the case; build lukS-PV and lukF- PV gene expression vector and corresponding proteins expressed in E. coli. Methods: From January 2006 to December 2008 during our hospital bloodstream infections caused clinical isolates of S. aureus strains (47), the source of the specimen are venous blood. Agar dilution method to detect all strains of antimicrobial resistance, PCR method to detect pvl gene application DiversiLabTM Rep-PCR strain typing system strain homology; methicillin-resistant Staphylococcus aureus ( Methicillin-resistant Staphylococcus aureus, MRSA) other rapid screening of staphylococcal chromosome mec (SCCmec) typing, pulsed-field gel electrophoresis (Pulse-field Electrophoresis, PFGE) typing and ST239 type; a comprehensive genotyping results and susceptibility The test results, the selection of some of the representative strains multilocus sequence typing (Multilocus Sequence Typing MLST). By molecular biology techniques, cloning and gene expression lukS-PV and lukF-PV. Results: 47 caused strains of S. aureus bloodstream infections, pvl detection rate of 4.3% (2/47). MRSA24 strains accounted for 51.1% of all MRSA were SCCmec Ⅲ type strain, of which 22 (91.67%), ST239; DiversiLabTM Rep-PCR strain typing system 47 Staphylococcus aureus is divided into A ~ L 12 type type A, the most important type of 22, accounting for 46.8% of all MRSA are two types of A, B; pulsed-field gel electrophoresis MRSA is divided into 6 A ~ F type, A-type A1 ~ A6 six subtypes, B type 2 subtype. Successfully cloned lukS-PV and lukF-PV genes, the recombinant expression the plasmid lukF-PV-pET28a () the the PV-pET28a to know lukS-(), expressed in E. coli BL21 recombinant protein was achieved initial success. Conclusion: The clinical bloodstream infections from January 2006 to December 2008 in our hospital separation methicillin-resistant Staphylococcus aureus Staphylococcus aureus vast majority of multi-drug resistant clones of MRSA-ST239-SCCmec Ⅲ type. These MRSA closer relationship at the molecular level, and some the wards may exist outbreak. Caused by Staphylococcus aureus bloodstream infections pvl gene detection rate is not high, for 4.3%: the success of the lukS-PV and lukF-PV gene cloning and preliminary expression of Panton-Valentine leukocidin (PVL) immunoassay lay the foundation of the method.