2v9y
From Proteopedia
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==Overview== | ==Overview== | ||
| - | BACKGROUND: The purine biosynthetic pathway in procaryotes enlists eleven, enzymes, six of which use ATP. Enzymes 5 and 6 of this pathway, formylglycinamide ribonucleotide (FGAR) amidotransferase (PurL) and, aminoimidazole ribonucleotide (AIR) synthetase (PurM) utilize ATP to, activate the oxygen of an amide within their substrate toward nucleophilic, attack by a nitrogen. AIR synthetase uses the product of PurL, formylglycinamidine ribonucleotide (FGAM) and ATP to make AIR, ADP and, P(i). RESULTS: The structure of a hexahistidine-tagged PurM has been, solved by multiwavelength anomalous diffraction phasing techniques using, protein containing 28 selenomethionines per asymmetric unit. The final, model of PurM consists of two crystallographically independent dimers and, four sulfates. The ... | + | BACKGROUND: The purine biosynthetic pathway in procaryotes enlists eleven, enzymes, six of which use ATP. Enzymes 5 and 6 of this pathway, formylglycinamide ribonucleotide (FGAR) amidotransferase (PurL) and, aminoimidazole ribonucleotide (AIR) synthetase (PurM) utilize ATP to, activate the oxygen of an amide within their substrate toward nucleophilic, attack by a nitrogen. AIR synthetase uses the product of PurL, formylglycinamidine ribonucleotide (FGAM) and ATP to make AIR, ADP and, P(i). RESULTS: The structure of a hexahistidine-tagged PurM has been, solved by multiwavelength anomalous diffraction phasing techniques using, protein containing 28 selenomethionines per asymmetric unit. The final, model of PurM consists of two crystallographically independent dimers and, four sulfates. The overall R factor at 2.5 A resolution is 19.2%, with an, R(free) of 26.4%. The active site, identified in part by conserved, residues, is proposed to be a long groove generated by the interaction of, two monomers. A search of the sequence databases suggests that the, ATP-binding sites between PurM and PurL may be structurally conserved., CONCLUSIONS: The first structure of a new class of ATP-binding enzyme, PurM, has been solved and a model for the active site has been proposed., The structure is unprecedented, with an extensive and unusual, sheet-mediated intersubunit interaction defining the active-site grooves., Sequence searches suggest that two successive enzymes in the purine, biosynthetic pathway, proposed to use similar chemistries, will have, similar ATP-binding domains. |
==About this Structure== | ==About this Structure== | ||
| - | 2V9Y is a | + | 2V9Y is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] with SO4 as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [http://en.wikipedia.org/wiki/Phosphoribosylformylglycinamidine_cyclo-ligase Phosphoribosylformylglycinamidine cyclo-ligase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=6.3.3.1 6.3.3.1] Structure known Active Site: AC1. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=2V9Y OCA]. |
==Reference== | ==Reference== | ||
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[[Category: transferase]] | [[Category: transferase]] | ||
| - | ''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Mon Nov 5 18:52:02 2007'' |
Revision as of 16:46, 5 November 2007
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HUMAN AMINOIMIDAZOLE RIBONUCLEOTIDE SYNTHETASE
Overview
BACKGROUND: The purine biosynthetic pathway in procaryotes enlists eleven, enzymes, six of which use ATP. Enzymes 5 and 6 of this pathway, formylglycinamide ribonucleotide (FGAR) amidotransferase (PurL) and, aminoimidazole ribonucleotide (AIR) synthetase (PurM) utilize ATP to, activate the oxygen of an amide within their substrate toward nucleophilic, attack by a nitrogen. AIR synthetase uses the product of PurL, formylglycinamidine ribonucleotide (FGAM) and ATP to make AIR, ADP and, P(i). RESULTS: The structure of a hexahistidine-tagged PurM has been, solved by multiwavelength anomalous diffraction phasing techniques using, protein containing 28 selenomethionines per asymmetric unit. The final, model of PurM consists of two crystallographically independent dimers and, four sulfates. The overall R factor at 2.5 A resolution is 19.2%, with an, R(free) of 26.4%. The active site, identified in part by conserved, residues, is proposed to be a long groove generated by the interaction of, two monomers. A search of the sequence databases suggests that the, ATP-binding sites between PurM and PurL may be structurally conserved., CONCLUSIONS: The first structure of a new class of ATP-binding enzyme, PurM, has been solved and a model for the active site has been proposed., The structure is unprecedented, with an extensive and unusual, sheet-mediated intersubunit interaction defining the active-site grooves., Sequence searches suggest that two successive enzymes in the purine, biosynthetic pathway, proposed to use similar chemistries, will have, similar ATP-binding domains.
About this Structure
2V9Y is a Single protein structure of sequence from Homo sapiens with SO4 as ligand. Active as Phosphoribosylformylglycinamidine cyclo-ligase, with EC number 6.3.3.1 Structure known Active Site: AC1. Full crystallographic information is available from OCA.
Reference
X-ray crystal structure of aminoimidazole ribonucleotide synthetase (PurM), from the Escherichia coli purine biosynthetic pathway at 2.5 A resolution., Li C, Kappock TJ, Stubbe J, Weaver TM, Ealick SE, Structure. 1999 Sep 15;7(9):1155-66. PMID:10508786
Page seeded by OCA on Mon Nov 5 18:52:02 2007
Categories: Homo sapiens | Phosphoribosylformylglycinamidine cyclo-ligase | Single protein | Arrowsmith, C.H. | Berg, S.Van.Den. | Berglund, H. | Busam, R. | Collins, R. | Consortium, Structural.Genomics. | Dahlgren, L.G. | Edwards, A. | Flodin, S. | Flores, A. | Graslund, S. | Hallberg, B.M. | Hammarstrom, M. | Herman, M.D. | Holmberg-Schiavone, L. | Johansson, I. | Kallas, A. | Karlberg, T. | Kotenyova, T. | Lehtio, L. | Moche, M. | Nordlund, P. | Nyman, T. | Persson, C. | Sagemark, J. | Stenmark, P. | Sundstrom, M. | Thorsell, A.G. | Tresaugues, L. | Weigelt, J. | Welin, M. | SO4 | Airs | Alternative splicing | Aminoimidazole ribonucleotide synthetase | Atp-binding | Gart | Ligase | Multifunctional enzyme | Nucleotide-binding | Phosphorylation | Polymorphism | Purine biosynthesis | Purine metabolism | Sgc | Structural genomics | Structural genomics consortium | Transferase
