| Δ3-Δ2-Enoyl-CoA isomerase from the yeast Saccharomyces cerevisiae: Molecular and structural characterization | ||
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The 3.3 Å structure of yeast enoyl-CoA isomerase complexed with octanoyl-CoA was solved by the molecular replacement method with the AmoRe program (Navaza 1994) using data from 8 to 4 Å. The 2.15 Å structure of the yeast Δ3-Δ2-enoyl-CoA isomerase monomer solved by the MAD method was used as the search model. Since the space group of the crystal was not certain, the solution was searched for by using the space groups P422, P4212, P4122, P4322, P4222, P42212, P41212 and P43212. The molecular replacement calculations only yielded solutions in the space group P41212. The coordinates of the octanoyl-CoA-complexed Eci1p trimer were first refined by rigid body refinement of each monomer with REFMAC (Murshudov et al. 1997) and then subjected to further restrained refinement with REFMAC by using loose non-crystallographic symmetry (NCS) restraints. The ligand, octanoyl-CoA, was also built into the active sites of the subunits and then refined using NCS restraints. The coordinates of octanoyl-CoA were taken from the 2-enoyl-CoA hydratase-1 structure (2DUB, Engel et al. 1998). In addition, two water molecules and three phosphate ions were added to the model. The coordinates were submitted to the pdb with the entry code 1K39.