Fig. 3

Expression and purification of R0.6C. a Schematic representation of expression and purification R0.6C fusion protein. Elution profiles of R0.6C on the b HisTrap HP and c HiTrap Q-HP-columns. Red line denotes UV absorbance (A280) and the black line denote antibody reactivity in the mAb45.1 sandwich ELISA. Selected fractions (5 µl) were analyzed on 4–12.5% polyacrylamide gels shown below the chromatograms. Protein was loaded without a reducing agent. The sizes (kDa) of the molecular mass markers are indicated. d Analysis of R0.6C. Left panel Coomassie blue-stained 4–12.5% polyacrylamide gel; 1 Supernatant, 2 HisTrap HP column and 3 HiTrap Q HP column purified R0.6C. Right panel an immune blot analysis of the same gel shown in the left panel using mAb45.1. Protein was loaded in each lane with (+) or without (−) DTT (10 mM). e Sandwich ELISA of conventionally (CP) and Immune (IP) purified R0.6C fusion proteins. Antigens were captured with mAb45.1 and detected with anti-His-HRP. X-axis is shown on a logarithmic scale