Reaction with iodoacetamide does not affect DNA-binding. Lane 1 is the radiolabeled EP24 DNA (5′-32P-GCTGCAGATTGCGCAATCTGCAGCGTGTGTGTGT-OH-3′) without protein. The gel shifts due to bacterial crude, iodoacetamide treated bacterial crude, purified GFP-C/EBP, and iodoacetamide treated purified GFP-C/EBP are shown in lanes 2, 3, 4, and 5, respectively. In the experiments 2 μL of the purified and crude proteins were used.