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2fpi
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(New page: 200px<br /><applet load="2fpi" size="450" color="white" frame="true" align="right" spinBox="true" caption="2fpi, resolution 2.700Å" /> '''Crystal structure o...) |
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| - | [[Image:2fpi.gif|left|200px]]<br /><applet load="2fpi" size=" | + | [[Image:2fpi.gif|left|200px]]<br /><applet load="2fpi" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="2fpi, resolution 2.700Å" /> | caption="2fpi, resolution 2.700Å" /> | ||
'''Crystal structure of pig GTP-specific succinyl-CoA synthetase from polyethylene glycol'''<br /> | '''Crystal structure of pig GTP-specific succinyl-CoA synthetase from polyethylene glycol'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Two isoforms of succinyl-CoA synthetase exist in mammals, one specific for | + | Two isoforms of succinyl-CoA synthetase exist in mammals, one specific for ATP and the other for GTP. The GTP-specific form of pig succinyl-CoA synthetase has been crystallized in the presence of GTP and the structure determined to 2.1 A resolution. GTP is bound in the ATP-grasp domain, where interactions of the guanine base with a glutamine residue (Gln-20beta) and with backbone atoms provide the specificity. The gamma-phosphate interacts with the side chain of an arginine residue (Arg-54beta) and with backbone amide nitrogen atoms, leading to tight interactions between the gamma-phosphate and the protein. This contrasts with the structures of ATP bound to other members of the family of ATP-grasp proteins where the gamma-phosphate is exposed, free to react with the other substrate. To test if GDP would interact with GTP-specific succinyl-CoA synthetase in the same way that ADP interacts with other members of the family of ATP-grasp proteins, the structure of GDP bound to GTP-specific succinyl-CoA synthetase was also determined. A comparison of the conformations of GTP and GDP shows that the bases adopt the same position but that changes in conformation of the ribose moieties and the alpha- and beta-phosphates allow the gamma-phosphate to interact with the arginine residue and amide nitrogen atoms in GTP, while the beta-phosphate interacts with these residues in GDP. The complex of GTP with succinyl-CoA synthetase shows that the enzyme is able to protect GTP from hydrolysis when the active-site histidine residue is not in position to be phosphorylated. |
==About this Structure== | ==About this Structure== | ||
| - | 2FPI is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Sus_scrofa Sus scrofa] with SO4 as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [http://en.wikipedia.org/wiki/Succinate--CoA_ligase_(GDP-forming) Succinate--CoA ligase (GDP-forming)], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=6.2.1.4 6.2.1.4] Full crystallographic information is available from [http:// | + | 2FPI is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Sus_scrofa Sus scrofa] with <scene name='pdbligand=SO4:'>SO4</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [http://en.wikipedia.org/wiki/Succinate--CoA_ligase_(GDP-forming) Succinate--CoA ligase (GDP-forming)], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=6.2.1.4 6.2.1.4] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2FPI OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Succinate--CoA ligase (GDP-forming)]] | [[Category: Succinate--CoA ligase (GDP-forming)]] | ||
[[Category: Sus scrofa]] | [[Category: Sus scrofa]] | ||
| - | [[Category: Fraser, M | + | [[Category: Fraser, M E.]] |
[[Category: SO4]] | [[Category: SO4]] | ||
[[Category: active site phosphohistidine residue]] | [[Category: active site phosphohistidine residue]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 17:23:48 2008'' |
Revision as of 15:23, 21 February 2008
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Crystal structure of pig GTP-specific succinyl-CoA synthetase from polyethylene glycol
Overview
Two isoforms of succinyl-CoA synthetase exist in mammals, one specific for ATP and the other for GTP. The GTP-specific form of pig succinyl-CoA synthetase has been crystallized in the presence of GTP and the structure determined to 2.1 A resolution. GTP is bound in the ATP-grasp domain, where interactions of the guanine base with a glutamine residue (Gln-20beta) and with backbone atoms provide the specificity. The gamma-phosphate interacts with the side chain of an arginine residue (Arg-54beta) and with backbone amide nitrogen atoms, leading to tight interactions between the gamma-phosphate and the protein. This contrasts with the structures of ATP bound to other members of the family of ATP-grasp proteins where the gamma-phosphate is exposed, free to react with the other substrate. To test if GDP would interact with GTP-specific succinyl-CoA synthetase in the same way that ADP interacts with other members of the family of ATP-grasp proteins, the structure of GDP bound to GTP-specific succinyl-CoA synthetase was also determined. A comparison of the conformations of GTP and GDP shows that the bases adopt the same position but that changes in conformation of the ribose moieties and the alpha- and beta-phosphates allow the gamma-phosphate to interact with the arginine residue and amide nitrogen atoms in GTP, while the beta-phosphate interacts with these residues in GDP. The complex of GTP with succinyl-CoA synthetase shows that the enzyme is able to protect GTP from hydrolysis when the active-site histidine residue is not in position to be phosphorylated.
About this Structure
2FPI is a Protein complex structure of sequences from Sus scrofa with as ligand. Active as Succinate--CoA ligase (GDP-forming), with EC number 6.2.1.4 Full crystallographic information is available from OCA.
Reference
Interactions of GTP with the ATP-grasp domain of GTP-specific succinyl-CoA synthetase., Fraser ME, Hayakawa K, Hume MS, Ryan DG, Brownie ER, J Biol Chem. 2006 Apr 21;281(16):11058-65. Epub 2006 Feb 15. PMID:16481318
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