2cdq
CRYSTAL STRUCTURE OF ARABIDOPSIS THALIANA ASPARTATE KINASE COMPLEXED WITH LYSINE AND S-ADENOSYLMETHIONINE
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OverviewOverview
Asp kinase catalyzes the first step of the Asp-derived essential amino, acid pathway in plants and microorganisms. Depending on the source, organism, this enzyme contains up to four regulatory ACT domains and, exhibits several isoforms under the control of a great variety of, allosteric effectors. We report here the dimeric structure of a Lys and, S-adenosylmethionine-sensitive Asp kinase isoform from Arabidopsis, thaliana in complex with its two inhibitors. This work reveals the, structure of an Asp kinase and an enzyme containing two ACT domains, cocrystallized with its effectors. Only one ACT domain (ACT1) is, implicated in effector binding. A loop involved in the binding of Lys and, S-adenosylmethionine provides an explanation for the synergistic, inhibition by these effectors. The presence of S-adenosylmethionine in the, regulatory domain indicates that ACT domains are also able to bind, nucleotides. The organization of ACT domains in the present structure is, different from that observed in Thr deaminase and in the regulatory, subunit of acetohydroxyacid synthase III.
About this StructureAbout this Structure
2CDQ is a Single protein structure of sequence from Arabidopsis thaliana with TAR, SAM and LYS as ligands. Active as Aspartate kinase, with EC number 2.7.2.4 Known structural/functional Site: . Full crystallographic information is available from OCA.
ReferenceReference
A novel organization of ACT domains in allosteric enzymes revealed by the crystal structure of Arabidopsis aspartate kinase., Mas-Droux C, Curien G, Robert-Genthon M, Laurencin M, Ferrer JL, Dumas R, Plant Cell. 2006 Jul;18(7):1681-92. Epub 2006 May 26. PMID:16731588
Page seeded by OCA on Tue Dec 18 19:18:36 2007