The fusion protein, 6XHis-Xpress-PedA was constructed and expressed in
Escherichia coli BL21 (DE3). The presence of a 12.8 kDa recombinant
protein, localized in inclusion bodies (IBs) at high concentration, was
confirmed by SDS-PAGE analysis and by western blotting using anti-His
antibody. The rec-pediocin was purified by Nickel-nitrilotriacetic acid
beads and refolded using 5 mM of \u3b2-mercaptoethanol along with 1 M
glycine. Results indicated that the refolded rec-pediocin had an early
elution profile in the RP-HPLC when compared to the unfolded protein
and it exhibited biological activity against Listeria monocytogenes
V7 which was approximately 25 times less active compared to native
counterpart. The final yield of purified rec-pediocin was 3 mg/l of the
culture and is estimated to be 8-10 times higher than the purification
by conventional methods