Optimal Expression of Recombinant Hybrid Enzyme SOD1/3 in E. coli

Objective To obtain recombinant hybrid enzyme SOD1/3 with higher activity in E.coli.Methods The recombinant bacteria containing expression plasmid pET-SOD1/3 was used to express hybrid enzyme SOD1/3.The effects of induction temperature,induction time,IPTG concentration and Cu2+ or Zn2+ concentration on the expression amount and activity of recombinant hybrid enzyme SOD1/3 were investigated by SDS-PAGE and SOD activity assay.Results When the recombinant bacteria were cultured at 15℃ for 12 h with 2.4 mmol/L Cu2+ or Zn2+ and 1 mmol/L IPTG at A600=1.2,the activity of hybrid enzyme SOD1/3 was higher with specific activity of 1 681U/mg.Conclusion The optimal expression of hybrid enzyme SOD1/3 is mainly affected by induction temperature and Cu2+ or Zn2+ concentration.Hybrid enzyme SOD1/3 can be expressed in supernatant at low temperature.The addition of Cu2+ or Zn2+ can increase the activity of hybrid enzyme SOD1/3.