FIGURE 2.

The CoA binding motif of ACOT12. A, the two potential binding sites for CoA on ACOT12, with binding site I occupied by CoA as demonstrated by density at both 2 and 5σ of F_o − F_c annealed omit maps and, in binding site II, a clear lack of density. B, the binding sites for CoA involving four separate binding regions; R1a (TAS⁵⁵), R1b (STS⁸⁴), R1c (Arg¹⁴⁴), and R1d (KRFG²³⁷) for binding site I, whereas the binding site II contains steric clashes inhibiting CoA from occupying this site. C, location of CoA binding and active site residues on ACOT12 and ACOT7, demonstrating domain swapping between these two thioesterases for these critical functional regions. D, surface representation of ACOT12 with CoA shown as sticks and the substrate-binding tunnel is shown as spheres determined using Caver (38).