2gqr
From Proteopedia
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| - | [[Image:2gqr.gif|left|200px]] | + | [[Image:2gqr.gif|left|200px]] |
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| - | '''SAICAR Synthetase Complexed with ADP-Mg2+''' | + | {{Structure |
| + | |PDB= 2gqr |SIZE=350|CAPTION= <scene name='initialview01'>2gqr</scene>, resolution 2.000Å | ||
| + | |SITE= | ||
| + | |LIGAND= <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene> and <scene name='pdbligand=ADP:ADENOSINE-5'-DIPHOSPHATE'>ADP</scene> | ||
| + | |ACTIVITY= [http://en.wikipedia.org/wiki/Phosphoribosylaminoimidazolesuccinocarboxamide_synthase Phosphoribosylaminoimidazolesuccinocarboxamide synthase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=6.3.2.6 6.3.2.6] | ||
| + | |GENE= purC ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=562 Escherichia coli]) | ||
| + | }} | ||
| + | |||
| + | '''SAICAR Synthetase Complexed with ADP-Mg2+''' | ||
| + | |||
==Overview== | ==Overview== | ||
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==About this Structure== | ==About this Structure== | ||
| - | 2GQR is a [ | + | 2GQR is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2GQR OCA]. |
==Reference== | ==Reference== | ||
| - | Nucleotide complexes of Escherichia coli phosphoribosylaminoimidazole succinocarboxamide synthetase., Ginder ND, Binkowski DJ, Fromm HJ, Honzatko RB, J Biol Chem. 2006 Jul 28;281(30):20680-8. Epub 2006 May 9. PMID:[http:// | + | Nucleotide complexes of Escherichia coli phosphoribosylaminoimidazole succinocarboxamide synthetase., Ginder ND, Binkowski DJ, Fromm HJ, Honzatko RB, J Biol Chem. 2006 Jul 28;281(30):20680-8. Epub 2006 May 9. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/16687397 16687397] |
[[Category: Escherichia coli]] | [[Category: Escherichia coli]] | ||
[[Category: Phosphoribosylaminoimidazolesuccinocarboxamide synthase]] | [[Category: Phosphoribosylaminoimidazolesuccinocarboxamide synthase]] | ||
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[[Category: purc]] | [[Category: purc]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Mar 20 17:07:54 2008'' |
Revision as of 15:07, 20 March 2008
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| , resolution 2.000Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | and | ||||||
| Gene: | purC (Escherichia coli) | ||||||
| Activity: | Phosphoribosylaminoimidazolesuccinocarboxamide synthase, with EC number 6.3.2.6 | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
SAICAR Synthetase Complexed with ADP-Mg2+
Overview
Phosphoribosylaminoimidazole-succinocarboxamide synthetase (SAICAR synthetase) converts 4-carboxy-5-aminoimidazole ribonucleotide (CAIR) to 4-(N-succinylcarboxamide)-5-aminoimidazole ribonucleotide (SAICAR). The enzyme is a target of natural products that impair cell growth. Reported here are the crystal structures of the ADP and the ADP.CAIR complexes of SAICAR synthetase from Escherichia coli, the latter being the first instance of a CAIR-ligated SAICAR synthetase. ADP and CAIR bind to the active site in association with three Mg(2+), two of which coordinate the same oxygen atom of the 4-carboxyl group of CAIR; whereas, the third coordinates the alpha- and beta-phosphoryl groups of ADP. The ADP.CAIR complex is the basis for a transition state model of a phosphoryl transfer reaction involving CAIR and ATP, but also supports an alternative chemical pathway in which the nucleophilic attack of l-aspartate precedes the phosphoryl transfer reaction. The polypeptide fold for residues 204-221 of the E. coli structure differs significantly from those of the ligand-free SAICAR synthetase from Thermatoga maritima and the adenine nucleotide complexes of the synthetase from Saccharomyces cerevisiae. Conformational differences between the E. coli, T. maritima, and yeast synthetases suggest the possibility of selective inhibition of de novo purine nucleotide biosynthesis in microbial organisms.
About this Structure
2GQR is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.
Reference
Nucleotide complexes of Escherichia coli phosphoribosylaminoimidazole succinocarboxamide synthetase., Ginder ND, Binkowski DJ, Fromm HJ, Honzatko RB, J Biol Chem. 2006 Jul 28;281(30):20680-8. Epub 2006 May 9. PMID:16687397
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