1I01: Crystal Structure Of Beta-ketoacyl [acyl Carrier Protein] Reductase From E. Coli

The structure of beta-ketoacyl-[acyl carrier protein] reductase (FabG) from Escherichia coli was determined via the multiwavelength anomalous diffraction technique using a selenomethionine-labeled crystal containing 88 selenium sites in the asymmetric unit. The comparison of the E. coli FabG structure with the homologous Brassica napus FabG.NADP(+) binary complex reveals that cofactor binding causes a substantial conformational change in the protein. This conformational change puts all three active-site residues (Ser 138, Tyr 151, and Lys 155) into their active configurations and provides a structural mechanism for allosteric communication between the active sites in the homotetramer. FabG exhibits negative cooperative binding of NADPH, and this effect is enhanced by the presence of acyl carrier protein (ACP). NADPH binding also increases the affinity and decreases the maximum binding of ACP to FabG. Thus, unlike other members of the short-chain dehydrogenase/reductase superfamily, FabG undergoes a substantial conformational change upon cofactor binding that organizes the active-site triad and alters the affinity of the other substrate-binding sites in the tetrameric enzyme.
PDB ID: 1I01Download
MMDB ID: 15257
PDB Deposition Date: 2001/1/27
Updated in MMDB: 2014/11
Experimental Method:
x-ray diffraction
Resolution: 2.6  Å
Source Organism:
Similar Structures:
Biological Unit for 1I01: tetrameric; determined by author and by software (PISA)
Molecular Components in 1I01
Label Count Molecule
Proteins (4 molecules)
Beta-ketoacyl [acp] Reductase(Gene symbol: fabG)
Molecule annotation
* Click molecule labels to explore molecular sequence information.

Citing MMDB