FIGURE 1.

Schematic summary of E. coli LigA contacts to DNA. The nicked duplex DNA is depicted as a two-dimensional schematic, with the continuous template strand on the left and the nicked strands on the right. The extrahelical 5′-adenylate is shown at right. The DNA contacts of LigA side chains (residue identity in plain text) and main-chain amides (residue identity in italics) are indicated by arrows. Amino acids making both main-chain and side-chain contacts to DNA are in bold font. Water-mediated interactions are shown with waters as red spheres. LigA residues that penetrate the DNA helix and interact with the bases are indicated within the DNA base pair ladder. A space-filling view of LigA bound to nicked DNA-adenylate is shown at the top right.