Abstract

For the expression of Staphylococcus aureus exfoliative toxin A in Escherichia coliregulated by a T5 promoter, the gene was amplified by polymerase chain reaction and cloned into expression vector pQE-30 to generate pQE-ETA. The maximum production of His6-tagged protein by E. coli M15 (PQE-ETA) was obtained with 0.1 mM IPTG induction for 4 h at 25°C. The expressed protein was purified by Ni²⁺-nitrilotriacetate resin to a specific activity of 0.25 mg/ml recombinant protein. The molecular mass of the purified protein was estimated to be 27 kDa by SDS-PAGE. Western blot showed that, the recombinant protein was recognized by sheep anti-ETA antibody and the recombinant protein could split the stratum granulosum of the mouse skin. In conclusion, it was found that the recombinant ETA exhibited no important differences from those properties described for the native protein.

Key words: Escherichia coli, exfoliative toxin A, Staphylococcus aureus.

Abbreviation

ET, exfoliative toxin; SSSS, staphylococcal scalded-skin syndrome;Dsg, desmoglein; LB, Luria-Bertani; PCR, polymerase chain reaction; IPTG,isopropyl-D-thiogalactopyranoside; SDS-PAGE, sodium dodecyl sulfate polyacrylamide gel electrophoresis; TEMED, N,N,N’N’-tetra methyl ethylene diamine; PVDF, Polyvinylidene difluoride; ECL, enhanced chemiluminescence.