Figure 1.

Model for the Mnt–operator interaction from Knight and Sauer (3) and Raumann et al. (8). Positions 3–19 are thought to include all of the direct interactions with the protein. The amino acids modeled to interact directly with the DNA are Arg2, His6, Asn8 and Arg10. The figure shows the two dimers, one underlined the other not, that each bind to one half-site. Each dimer contains an anti-parallel β-ribbon of the N-terminal amino acids. Amino acids R2, H6 and N8 from one monomer of each dimer (in blue) and amino acids N8 and R10 of the other monomer (in green) are thought to interact with the base pairs indicated.