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1b6r

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Revision as of 11:01, 10 September 2015

N5-CARBOXYAMINOIMIDAZOLE RIBONUCLEOTIDE SYNTHETASE FROM E. COLI

Structural highlights

1b6r is a 1 chain structure with sequence from Escherichia coli. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Ligands:
Activity:	Phosphoribosylaminoimidazole carboxylase, with EC number 4.1.1.21
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum

Function

[PURK_ECOLI] Catalyzes the ATP-dependent conversion of 5-aminoimidazole ribonucleotide (AIR) and HCO(3)(-) to N5-carboxyaminoimidazole ribonucleotide (N5-CAIR).

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

Escherichia coli PurK, a dimeric N5-carboxyaminoimidazole ribonucleotide (N5-CAIR) synthetase, catalyzes the conversion of 5-aminoimidazole ribonucleotide (AIR), ATP, and bicarbonate to N5-CAIR, ADP, and Pi. Crystallization of both a sulfate-liganded and the MgADP-liganded E. coli PurK has resulted in structures at 2.1 and 2.5 A resolution, respectively. PurK belongs to the ATP grasp superfamily of C-N ligase enzymes. Each subunit of PurK is composed of three domains (A, B, and C). The B domain contains a flexible, glycine-rich loop (B loop, T123-G130) that is disordered in the sulfate-PurK structure and becomes ordered in the MgADP-PurK structure. MgADP is wedged between the B and C domains, as with all members of the ATP grasp superfamily. Other enzymes in this superfamily contain a conserved Omega loop proposed to interact with the B loop, define the specificity of their nonnucleotide substrate, and protect the acyl phosphate intermediate formed from this substrate. PurK contains a minimal Omega loop without conserved residues. In the reaction catalyzed by PurK, carboxyphosphate is the putative acyl phosphate intermediate. The sulfate of the sulfate ion-liganded PurK interacts electrostatically with Arg 242 and the backbone amide group of Asn 245, components of the J loop of the C domain. This sulfate may reveal the location of the carboxyphosphate binding site. Conserved residues within the C-terminus of the C domain define a pocket that is proposed to bind AIR in collaboration with an N-terminal strand loop helix motif in the A domain (P loop, G8-L1). The P loop is proposed to bind the phosphate of AIR on the basis of similar binding sites observed in PurN and PurE and proposed in PurD and PurT, four other enzymes in the purine pathway.

Three-dimensional structure of N5-carboxyaminoimidazole ribonucleotide synthetase: a member of the ATP grasp protein superfamily.,Thoden JB, Kappock TJ, Stubbe J, Holden HM Biochemistry. 1999 Nov 23;38(47):15480-92. PMID:10569930^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Thoden JB, Kappock TJ, Stubbe J, Holden HM. Three-dimensional structure of N5-carboxyaminoimidazole ribonucleotide synthetase: a member of the ATP grasp protein superfamily. Biochemistry. 1999 Nov 23;38(47):15480-92. PMID:10569930

1 Structural highlights
2 Function
3 Evolutionary Conservation
4 Publication Abstract from PubMed
5 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/1b6r"

@@ Line 5: / Line 5: @@
 </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene></td></tr>
 <tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Phosphoribosylaminoimidazole_carboxylase Phosphoribosylaminoimidazole carboxylase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=4.1.1.21 4.1.1.21] </span></td></tr>
-<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1b6r FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1b6r OCA], [http://www.rcsb.org/pdb/explore.do?structureId=1b6r RCSB], [http://www.ebi.ac.uk/pdbsum/1b6r PDBsum]</span></td></tr>
+<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1b6r FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1b6r OCA], [http://pdbe.org/1b6r PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1b6r RCSB], [http://www.ebi.ac.uk/pdbsum/1b6r PDBsum]</span></td></tr>
 </table>
 == Function ==
@@ Line 27: / Line 27: @@
 From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
 </div>
+<div class="pdbe-citations 1b6r" style="background-color:#fffaf0;"></div>
 == References ==
 <references/>

1b6r

From Proteopedia

Revision as of 11:01, 10 September 2015

N5-CARBOXYAMINOIMIDAZOLE RIBONUCLEOTIDE SYNTHETASE FROM E. COLI

Structural highlights

Function

Evolutionary Conservation

Publication Abstract from PubMed

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

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