3r5h | pdb_00003r5h

Crystal Structure of ADP-AIR complex of purK: N5-carboxyaminoimidazole ribonucleotide synthetase

spinqualitylabelsall models 3r5h, resolution 2.20Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image   Print3D Structural highlights 3r5h is a 2 chain structure with sequence from Bacaa. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Ligands: ADP, AIR, MG Gene: BAA_0344, purK (BACAA) Activity: Phosphoribosylaminoimidazole carboxylase, with EC number 4.1.1.21 Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Publication Abstract from PubMed Structures of (N(5))-carboxyaminoimidazole ribonucleotide synthase (PurK) from Bacillus anthracis with various combinations of ATP, ADP, Mg(2+), bicarbonate and aminoimidazole ribonucleotide (AIR) in the active site are presented. The binding site of bicarbonate has only been speculated upon previously, but is shown here for the first time. The binding involves interactions with the conserved residues Arg272, His274 and Lys348. These structures provide insights into each ligand in the active site and allow a possible mechanism to be proposed for the reaction that converts bicarbonate and AIR, in the presence of ATP, to produce (N(5))-carboxyaminoimidazole ribonucleotide. The formation of a carboxyphosphate intermediate through ATP phosphoryl transfer is proposed, followed by carboxylation of AIR to give the product, facilitated by a cluster of conserved residues and an active-site water network. Elucidation of the bicarbonate binding site and insights into the carboxylation mechanism of (N(5))-carboxyaminoimidazole ribonucleotide synthase (PurK) from Bacillus anthracis.,Tuntland ML, Santarsiero BD, Johnson ME, Fung LW Acta Crystallogr D Biol Crystallogr. 2014 Nov;70(Pt 11):3057-65. doi:, 10.1107/S1399004714021166. Epub 2014 Oct 29. PMID:25372694 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

Proteopedia Page Contributors and Editors (what is this?)

OCA