SDS-PAGE analysis of hAD expression in the BL21 (DE3) and DH5α E.coli strains. (A) Expression of hAD tested in DH5α E.coli, samples labeled as U were uninduced culture while I represented 1mM IPTG 4-hours induced culture. (B) Expression of hAD tested in BL21 (DE3) E. coli. (C) SDS-PAGE result of hAD recombinant protein expression bacteria strains B3 and D1 uninduced-induced samples and expression formats. Recombinant hAD expressed well, with considerable amount of protein being retained in the soluble fractions. (D) Purification results of hAD yielded from 250mL culture under the same conditions and compared with BSA protein standard.