SDS-PAGE showing expression and purification of P48 in E. coli . All protein was subjected to 8-12% SDS-PAGE analysis and the gel was stained with Coomassie blue. M: prestained protein molecular weight marker (10-170 KDa), lane 1-3: total cell lysates of Transetta (DE3), Transetta (DE3) with PET28 (a+) plasmid, Transetta (DE3) with PET28 (a+)-P48 gene plasmid. Proteins were extracted after 1 mM IPTG induction for 6 h. Lane 4: purified P48 protein using His · Bind kits. Approximately 50 kDa protein band with a purity of 95% was observed.