Enhancing expression level of recombinant antigen 3-1E of Eimeria in Escherichia coli BL21 (DE3)

Abstract

Improvement of the recombinant antigen expression level in E. coli strain BL21 StarTM(DE3) encoding gene 3-1E of Eimeria was conducted. The studied result showed that LB medium has given the best growth of E. coli BL21 (DE3) in comparison with other media in the same 2 % initial seed inoculum size (OD600 = 0,8), shaking 200 rpm at 370C for 11 hrs. However, the highest level of fusion protein (6xHis-3-1E) was obtained from YJ medium in the same optimum culture condition (0.8 mM IPGT-Isopropyl β-D-1-thiogalactopyranoside for 10hrs. at 20oC). Molecular weight of purified 6xHis-3-1E protein from 6xHis affinity chromatography was about 26 kDa.