FIG. 2.
Interaction between RsbA and σB monitored by affinity chromatography. His-tagged σB and GST-RsbA in binding buffer were applied to an Ni-NTA column as described in Materials and Methods (ON; lane 2). Fractions from flow-through (FT; lane 3), wash with 5 mM imidazole (W1; lane 4), wash with 25 mM imidazole (W2; lane 5), W2), and elution with 500 mM imidazole (E; lane 6) were pooled, concentrated, and subjected to SDS-PAGE. Proteins were visualized by Coomassie staining and marked along with size markers (M; lane 1) of 66 and 41 kDa.