2DTJ

Crystal structure of regulatory subunit of aspartate kinase from Corynebacterium glutamicum

Summary for 2DTJ

• Entry DOI: 10.2210/pdb2dtj/pdb
• Related: 2DT9
• Descriptor: Aspartokinase, THREONINE, CITRIC ACID, ... (4 entities in total)
• Functional Keywords: protein-ligand complex, regulatory subunit, transferase
• Biological source: Corynebacterium glutamicum
• Total number of polymer chains: 2
• Total formula weight: 39199.87

Authors

Yoshida, A.,Tomita, T.,Fushinobu, S.,Kuzuyama, T.,Nishiyama, M. (deposition date: 2006-07-12, release date: 2007-05-01, Last modification date: 2023-11-08)

Primary citation

Yoshida, A.,Tomita, T.,Kurihara, T.,Fushinobu, S.,Kuzuyama, T.,Nishiyama, M.
Structural Insight into Concerted Inhibition of alpha(2)beta(2)-Type Aspartate Kinase from Corynebacterium glutamicum
J.Mol.Biol., 368:521-536, 2007

PubMed Abstract: 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.

PubMed: 17350037
DOI: 10.1016/j.jmb.2007.02.017

Experimental method

X-RAY DIFFRACTION (1.58 Å)