2dtj
Crystal structure of regulatory subunit of aspartate kinase from Corynebacterium glutamicum
| |||||||
| , resolution 1.58Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | , | ||||||
| Activity: | Aspartate kinase, with EC number 2.7.2.4 | ||||||
| Related: | 2DT9
| ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
OverviewOverview
Aspartate kinase (AK) catalyzes the first step of the biosynthesis of the aspartic acid family amino acids, and is regulated via feedback inhibition by end-products including Thr and Lys. To elucidate the mechanism of this inhibition, we determined the crystal structure of the regulatory subunit of AK from Corynebacterium glutamicum at 1.58 A resolution in the Thr-binding form, the first crystal structure of the regulatory subunit of alpha(2)beta(2)-type AK. The regulatory subunit contains two ACT domain motifs per monomer and is arranged as a dimer. Two non-equivalent ACT domains from different chains form an effector-binding unit that binds a single Thr molecule, and the resulting two effector-binding units of the dimer associate perpendicularly in a face-to-face manner. The regulatory subunit is a monomer in the absence of Thr but becomes a dimer by adding Thr. The dimerization is eliminated in mutant AKs with changes in the Thr-binding region, suggesting that the dimerization induced by Thr binding is a key step in the inhibitory mechanism of AK from C. glutamicum. A putative Lys-binding site and the inhibitory mechanism of CgAK are discussed.
About this StructureAbout this Structure
2DTJ is a Single protein structure of sequence from Corynebacterium glutamicum. Full crystallographic information is available from OCA.
ReferenceReference
Structural Insight into concerted inhibition of alpha 2 beta 2-type aspartate kinase from Corynebacterium glutamicum., Yoshida A, Tomita T, Kurihara T, Fushinobu S, Kuzuyama T, Nishiyama M, J Mol Biol. 2007 Apr 27;368(2):521-36. Epub 2007 Feb 20. PMID:17350037
Page seeded by OCA on Mon Mar 31 02:39:15 2008