Figure 2.

HEL protein and mutant purification. (a) Crystal structure of HEL-Fv complex showing three residues, R21, R73, and D101 in HEL that are important for binding to the transgenic BCR, IgHEL (PDB 1c08). These three residues are highlighted in spacing-filling model. The C-terminus of the HEL protein is also denoted. (b) Silver staining of a 15% (29:1 acrylamide/Bis) reducing SDS–polyacrylamide gel to assess the purity of the purified proteins wtHEL, HELD, HELT, HELDC, and HELTC. For each protein, three lanes were loaded at 2%, 5%, and 100% relative to the quantity of each purified protein, respectively.