Structure of an MltR monomer.

<p>(A) Ribbon diagram of MltR (left). The structure is colored by functional domains; red: DNA-binding (DBD), green: linker, and blue: ligand-binding (LBD). Helices are labeled from H1 to H14, and strands S1 to S6. The myristic acid (MYR) is shown as a ball-and-stick representation with carbons in yellow and oxygens in red. A topology diagram is shown on the right with helices in red and strands in green. The secondary structural elements that are absent in prototypical PAS domains are highlighted in cyan. (B) Protein sequence of MltR annotated with the corresponding secondary structure elements on the top (n.b. the 3₁₀ helices are colored red, but not labeled). Residues involved in dimer interface and ligand interactions are marked on the bottom by letters “D” and “L” respectively.