High Efficiency Expression Of Recombinant Staphylococcus Aureus RAP Protein In Escherichia Coli And Detection Its Activity In Vivo

OBJECTIVE To construct recombinant RAP protein expression vector of Staphylococcus aureus , to investigate its expression in E. coli and purification and to detect its activity in vivo.METHODS The target DNA fragment encoding the RAP protein of Staphylococcus aureus was amplified from the total DNA by polymerase chain reaction(PCR). E. coli TG₁ was transformed and its plasmid sequence was detected. The PCR product was then cloned into the expression plasmid vector pQE30 with 6xHis and transformed into E. coli SG13009 to express the recombinant protein. The protein was purified by Ni-NTA column. Then the protein was inoculated subcutaneously in mice to detect whether RAP can prevent the infection of S. aureus. RESULTS After inducing by IPTG, the recombinant RAP protein was expressed characterized by molecular mass about 40KD by SDS-PAGE. RAP can decrease the incidence rate of infection and relieve the infection.CONCLUSIONS The recombinant RAP protein was successfully expressed and purified and can prevent the infection caused by S. aureus. It could be one of the S. aureus vaccines.