Enhanced expression of recombinant beta toxin of Clostridium perfringens type B using a commercially available Escherichia coli strain

Clostridium perfringens beta toxin is only produced by types B and C and plays an important role in many human and animal diseases, causing fatal conditions that originate in the intestines. We compared the expression of C. perfringens type B vaccine strain recombinant beta toxin gene in the Escherichia coli strains Rosetta (TM)(DE3) and BL21(DE3). The beta toxin gene was extracted from pJET beta and ligated with pET22b(+). pET22 beta was transformed into E. coli strains BL21(DE3) and Rosetta (TM)(DE3). Recombinant protein was expressed as a soluble protein after isopropyl beta-D-1-thiogalactopyranoside (IPTG) induction in strain Rosetta (TM)(DE3) but not in BL21(DE3). Expression was optimised by growing recombinant cells at 37 degrees C and at an induction of 0.5 mM, 1 mM, 1.5 mM IPTG. Expression was evaluated using sodium dodecyl sulfate Polyacrylamide gel electrophoresis (SDS-PAGE). The recombinant protein was purified via Ni-NTA and was analysed using western blot. We concluded that E. coli strain Rosetta (TM)(DE3) can enhance the expression of C. perfringens recombinant beta toxin.