Fig. 3
Expression and purification of CeA peptide in CF system. a Different Mg2+ ion concentrations (12–22 mM) were tested to optimize His6–CeA production in the CF system. The supernatant and pellet fractions of RM were separated by centrifugation at 12,000 g for 5 min and analyzed with tricine SDS–PAGE stained with Coomassie Blue. S, supernatant samples; P, pellet samples. Red frame contains the band of CeA peptide, processed with high gray-scale resolution. b Purification of His6–CeA with Ni2+-NTA affinity chromatography. SL, samples containing His6–CeA before purification; FF, flow-through fraction; ET (1–4), elution fractions with imidazole; M1, M2, different protein markers, in kDa