4XB2: Hyperthermophilic Archaeal Homoserine Dehydrogenase Mutant In Complex With Nadph

NAD(P)-dependent dehydrogenases differ according to their coenzyme preference: some prefer NAD, others NADP, and still others exhibit dual cofactor specificity. The structure of a newly identified archaeal homoserine dehydrogenase showed this enzyme to have a strong preference for NADP. However, NADP did not act as a cofactor with this enzyme, but as a strong inhibitor of NAD-dependent homoserine oxidation. Structural analysis and site-directed mutagenesis showed that the large number of interactions between the cofactor and the enzyme are responsible for the lack of reactivity of the enzyme towards NADP. This observation suggests this enzyme exhibits a new variation on cofactor binding to a dehydrogenase: very strong NADP binding that acts as an obstacle to NAD(P)-dependent dehydrogenase catalytic activity.
PDB ID: 4XB2Download
MMDB ID: 130922
PDB Deposition Date: 2014/12/16
Updated in MMDB: 2015/07
Experimental Method:
x-ray diffraction
Resolution: 2.43  Å
Source Organism:
Similar Structures:
Biological Unit for 4XB2: dimeric; determined by author and by software (PISA)
Molecular Components in 4XB2
Label Count Molecule
Proteins (2 molecules)
319aa Long Hypothetical Homoserine Dehydrogenase
Molecule annotation
Chemicals (6 molecules)
* Click molecule labels to explore molecular sequence information.

Citing MMDB