2dtj
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Crystal structure of regulatory subunit of aspartate kinase from Corynebacterium glutamicum
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 with and as ligands. Active as Aspartate kinase, with EC number 2.7.2.4 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
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