2v4y

THE STRUCTURE OF E. COLI UMP KINASE IN COMPLEX WITH ITS ALLOSTERIC REGULATOR GTP

spinqualitylabelsall models 2v4y, resolution 2.80Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image   Print3D Structural highlights 2v4y is a 6 chain structure with sequence from Escherichia coli K-12. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Method: X-ray diffraction, Resolution 2.8Å Ligands: GTP Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Function PYRH_ECOLI Catalyzes the reversible phosphorylation of UMP to UDP, with ATP as the most efficient phosphate donor. Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMed Bacterial UMP kinases are essential enzymes involved in the multistep synthesis of UTP. They are hexamers regulated by GTP (allosteric activator) and UTP (inhibitor). We describe here the 2.8 angstroms crystal structure of Escherichia coli UMP kinase bound to GTP. The GTP-binding site, situated at 15 angstroms from the UMP-binding site and at 24 angstroms from the ATP-binding site, is delineated by two contiguous dimers. The overall structure, as compared with those bound to UMP, UDP, or UTP, shows a rearrangement of its quaternary structure: GTP induces an 11 degrees opening of the UMP kinase dimer, resulting in a tighter dimer-dimer interaction. A nucleotide-free UMP kinase dimer has an intermediate opening. Superposition of our structure with that of archaeal UMP kinases, which are also hexamers, shows that a loop appears to hamper any GTP binding in archeal enzymes. This would explain the absence of activating effect of GTP on this group of UMP kinases. Among GTP-binding residues, the Asp-93 is the most conserved in bacterial UMP kinases. In the previously published structures of E. coli UMP kinase, this residue was shown to be involved in hydrogen bonds between the subunits of a dimer. Its substitution by an alanine decreases the cooperativity for UTP binding and suppresses the reversal by GTP of UTP inhibition. This demonstrates that the previously described mutual exclusion of these two nucleotides is mediated by Asp-93. Structural and functional characterization of Escherichia coli UMP kinase in complex with its allosteric regulator GTP.,Meyer P, Evrin C, Briozzo P, Joly N, Barzu O, Gilles AM J Biol Chem. 2008 Dec 19;283(51):36011-8. Epub 2008 Oct 22. PMID:18945668 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See Also Uridylate kinase

Proteopedia Page Contributors and Editors (what is this?)

OCA