Figure 2.

Protein purification of the sodium borohydride trapping-active protein. The borohydride-trapping active protein was purified from E. coli mutM nth nei mutant extract by standard chromatography techniques. Proteins from each purification step were separated by 12% SDS–PAGE and stained with Coomassie Blue. Lanes 1 and 8, molecular weight marker; Lane 2, crude extract; lane 3, Hi-Trap SP; lane 4, Hi-Trap Heparin; lane 5, HiTrap-Blue; lane 6, Hydroxyapatite; lane 7, Resource S. The arrow indicates the band for the candidate protein (trapping-active) used for determination of the N-terminal amino acid sequence.