Fig. 4.

Crystal structure of LuxD, the myristoyl-ACP-specific thioesterase from V. harveyi (PDB 1THT). Panel A shows the cartoon representation of LuxD in purple color with residues of the catalytic triad as stick models. The flexible hairpin element above the catalytic serine residue is colored in light red. Panels B and C feature the same coloration according to evolutionary conservation of residues introduced in Fig. 3. Highly conserved residues of the whole surface region around the fatty acid binding site support its involvement in complex formation with LuxE and/or LuxC (see below).