Fig. 3.

DNA strand separation by CcrM. a, b CcrM dimer contains two closed holes for the two separated DNA strands. The surface charge at neutral pH is displayed as blue for positive, red for negative, and white for neutral. c Pro45 of Loop-2B wedges into thymine bases T2 and T3 of the non-target strand. d A network of protein-protein interactions centered on DNA major groove, DNA minor groove, and through the space between the two strands including three pairs of polar interactions involving side chains of Asn47, Lys126, and Arg268 and the main-chain carbonyl oxygen atoms of Ala328, Leu43, and Lys126, respectively. e View from DNA minor groove side, with residues of molecule B (cyan) and molecule A (green) occupying the space between two strands