1ibs | pdb_00001ibs

PHOSPHORIBOSYLDIPHOSPHATE SYNTHETASE IN COMPLEX WITH CADMIUM IONS

spinqualitylabelsall models 1ibs, resolution 2.80Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image   Print3D Structural highlights 1ibs is a 2 chain structure with sequence from "vibrio_subtilis"_ehrenberg_1835 "vibrio subtilis" ehrenberg 1835. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Ligands: ABM, CD, SO4 Related: 1dkr, 1dku Gene: PRS ("Vibrio subtilis" Ehrenberg 1835) Activity: Ribose-phosphate diphosphokinase, with EC number 2.7.6.1 Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT 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 The binding sites for the two cations essential for the catalytic function of 5-phospho-D-ribosyl alpha-1-diphosphate (PRPP) synthases have been identified from the structure of the Bacillus subtilis phosphoribosyldiphosphate synthetase (PRPPsase) with bound Cd(2+). The structure determined from X-ray diffraction data to 2.8-A resolution reveals the same hexameric arrangement of the subunits that was observed in the complexes of the enzyme with the activator sulfate and the allosteric inhibitor ADP. Two cation binding sites were localized in each of the two domains of the subunits that compose the hexamer; each domain of the subunit has an associated cation. In addition to the bound Cd(2+), the Cd(2+)-PRPPsase structure contains a sulfate ion in the regulatory site, a sulfate ion at the ribose-5-phosphate binding site, and an AMP moiety at the ATP binding site. Comparison of the Cd(2+)-PRPPsase to the structures of the PRPPsase complexed with sulfate and mADP reveals the structural rearrangement induced by the binding of the free cation, which is essential for the initiation of the reaction. The comparison to the cPRPP complex of glutamine phosphoribosylpyrophosphate amidotransferase from Escherichia coli, a type I phosphoribosyltransferase, provided information about the binding of PRPP. This strongly indicates that the binding of both substrates must lead to a stabilized conformation of the loop region, which remains unresolved in the known PRPPsase complex structures. Binding of cations in Bacillus subtilis phosphoribosyldiphosphate synthetase and their role in catalysis.,Eriksen TA, Kadziola A, Larsen S Protein Sci. 2002 Feb;11(2):271-9. PMID:11790837 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

Proteopedia Page Contributors and Editors (what is this?)

OCA