Figure 2.

(a) Cross-linking of thioredoxin-tagged CLAMP derivatives using increasing concentrations of glutaraldehyde (GA). Uncropped images are shown in Figure S3. (b) Superdex S200 size-exclusion chromatography of CLAMP ^1–127 and CLAMP^1–153. Molecular weights of the monomers are shown in brackets. (c) Testing of the dimerization specificity of CLAMP deletion derivatives in glutathione S-transferase (GST). CLAMP derivatives fused either with GST or with 6xHis-thioredoxin were co-expressed in bacteria cells and affinity-purified with glutathione resin (which binds GST-tagged proteins). 6xHis pull-down assays are shown in Figure S4. Co-purified proteins were visualized with SDS-PAGE followed by Coomassie staining. Uncropped images are shown in Figure S4. (d) Summary of dimeric interactions observed with pull-down and cross-linking assays.