Fig. 1: Ligands bind without dramatic structural changes in the core domain to control the structure of the DNA-binding domain allosterically. | Nature Communications

Fig. 1: Ligands bind without dramatic structural changes in the core domain to control the structure of the DNA-binding domain allosterically.

From: Ligand-specific changes in conformational flexibility mediate long-range allostery in the lac repressor

Fig. 1

A X-ray crystal structure of dimeric LacI bound to the DNA operator. One subunit is shown in color (green: C-terminal subdomain; yellow: N-terminal subdomain; purple: DNA-binding domain) and the other subunit is shown in gray. PDB ID: 1EFA (ONPF-bound LacI without the tetramerization helix). B Overlaid structures of the core domains show similar backbone structures for apo-LacI (dark gray), IPTG-LacI (green, yellow, maroon), and ONPF-LacI (blue). PDB IDs: 1LBI (apo LacI core domain with tetramerization helix), 2P9H (IPTG-bound LacI core domain), 2PAF (ONPF-bound LacI core domain). C Overlaid structures of the ligand binding site in IPTG-LacI and ONPF-LacI reveal similar sidechain-atom positions, colored as in B. Thin sticks show amino acid sidechains. Thick sticks show ligands. D Chemical structures of ONPF, IPTG, and TMG with binding affinities to full-length LacI.

Back to article page