Fusion expression and purification of antitumor 19 peptide in E.coli

The recombinant vector pet32a- 19 peptides were transformed into E.coli. The induced expression conditions of the recombinant protein in E.coli was optimized by shaking flasks experiments. The recombinant protein was purified by Ni Sepharose 6 Fast Flow and refolding by gradient dialysis.The results showed that the pet32a-19 peptides- BL21( DE3) strain of high expression was obtained. By using the ferment condition the expression of protein reached 54.57 mg /L,which the highest level of the protein expression,the ferment condition was as follows: the pH of medium was 7.0,the inoculation amount was 3%,at value of 0.7 OD culture to add 0.1mmol/L IPTG,induced temperature was 41℃ and the induced time was 5h.The refolding of recombinant protein was succeed,and got more than 95% purity of the fusion antitumor 19 peptide.