(A and B) SDS-PAGE with Coomassia blue staining (A) and Western blot analysis (B) of recombinant Mgfp-5 from E. coli BL21. Lanes: M, protein molecular mass marker; N, whole-cell sample of the BL21 strain that harbors the parent vector pTrcHisA (negative control); WC, whole-cell sample; S, soluble supernatant fraction; IS, insoluble cell debris fraction. Recombinant cells were cultured in LB medium at 37°C with shaking at 250 rpm. (C) SDS-PAGE analysis, with silver staining, of immobilized metal affinity purification fractions. Lanes: M, protein molecular mass marker; 1, flowthrough fraction; 2, washout fraction; 3, eluted fraction. (D) MALDI-TOF mass spectrometry analysis of purified recombinant Mgfp-5. We used 15% polyacrylamide gels for all analyses. Monoclonal anti-hexahistidine antibody was used for the Western blot analysis.