1dqx
From Proteopedia
(New page: 200px<br /><applet load="1dqx" size="450" color="white" frame="true" align="right" spinBox="true" caption="1dqx, resolution 2.40Å" /> '''CRYSTAL STRUCTURE OF...) |
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| - | [[Image:1dqx.jpg|left|200px]]<br /><applet load="1dqx" size=" | + | [[Image:1dqx.jpg|left|200px]]<br /><applet load="1dqx" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1dqx, resolution 2.40Å" /> | caption="1dqx, resolution 2.40Å" /> | ||
'''CRYSTAL STRUCTURE OF OROTIDINE 5'-PHOSPHATE DECARBOXYLASE COMPLEXED TO 6-HYDROXYURIDINE 5'-PHOSPHATE (BMP)'''<br /> | '''CRYSTAL STRUCTURE OF OROTIDINE 5'-PHOSPHATE DECARBOXYLASE COMPLEXED TO 6-HYDROXYURIDINE 5'-PHOSPHATE (BMP)'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Orotidine 5'-phosphate decarboxylase produces the largest rate enhancement | + | Orotidine 5'-phosphate decarboxylase produces the largest rate enhancement that has been reported for any enzyme. The crystal structure of the recombinant Saccharomyces cerevisiae enzyme has been determined in the absence and presence of the proposed transition state analog 6-hydroxyuridine 5'-phosphate, at a resolution of 2.1 A and 2.4 A, respectively. Orotidine 5'-phosphate decarboxylase folds as a TIM-barrel with the ligand binding site near the open end of the barrel. The binding of 6-hydroxyuridine 5'-phosphate is accompanied by protein loop movements that envelop the ligand almost completely, forming numerous favorable interactions with the phosphoryl group, the ribofuranosyl group, and the pyrimidine ring. Lysine-93 appears to be anchored in such a way as to optimize electrostatic interactions with developing negative charge at C-6 of the pyrimidine ring, and to donate the proton that replaces the carboxylate group at C-6 of the product. In addition, H-bonds from the active site to O-2 and O-4 help to delocalize negative charge in the transition state. Interactions between the enzyme and the phosphoribosyl group anchor the pyrimidine within the active site, helping to explain the phosphoribosyl group's remarkably large contribution to catalysis despite its distance from the site of decarboxylation. |
==About this Structure== | ==About this Structure== | ||
| - | 1DQX is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Saccharomyces_cerevisiae Saccharomyces cerevisiae] with BMP as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [http://en.wikipedia.org/wiki/Orotidine-5'-phosphate_decarboxylase Orotidine-5'-phosphate decarboxylase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=4.1.1.23 4.1.1.23] Full crystallographic information is available from [http:// | + | 1DQX is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Saccharomyces_cerevisiae Saccharomyces cerevisiae] with <scene name='pdbligand=BMP:'>BMP</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [http://en.wikipedia.org/wiki/Orotidine-5'-phosphate_decarboxylase Orotidine-5'-phosphate decarboxylase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=4.1.1.23 4.1.1.23] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1DQX OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Saccharomyces cerevisiae]] | [[Category: Saccharomyces cerevisiae]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Hassell, A | + | [[Category: Hassell, A M.]] |
| - | [[Category: Milburn, M | + | [[Category: Milburn, M V.]] |
| - | [[Category: Miller, B | + | [[Category: Miller, B G.]] |
| - | [[Category: Short, S | + | [[Category: Short, S A.]] |
[[Category: Wolfenden, R.]] | [[Category: Wolfenden, R.]] | ||
[[Category: BMP]] | [[Category: BMP]] | ||
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[[Category: uridine 5'phosphate]] | [[Category: uridine 5'phosphate]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 12:19:30 2008'' |
Revision as of 10:19, 21 February 2008
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CRYSTAL STRUCTURE OF OROTIDINE 5'-PHOSPHATE DECARBOXYLASE COMPLEXED TO 6-HYDROXYURIDINE 5'-PHOSPHATE (BMP)
Overview
Orotidine 5'-phosphate decarboxylase produces the largest rate enhancement that has been reported for any enzyme. The crystal structure of the recombinant Saccharomyces cerevisiae enzyme has been determined in the absence and presence of the proposed transition state analog 6-hydroxyuridine 5'-phosphate, at a resolution of 2.1 A and 2.4 A, respectively. Orotidine 5'-phosphate decarboxylase folds as a TIM-barrel with the ligand binding site near the open end of the barrel. The binding of 6-hydroxyuridine 5'-phosphate is accompanied by protein loop movements that envelop the ligand almost completely, forming numerous favorable interactions with the phosphoryl group, the ribofuranosyl group, and the pyrimidine ring. Lysine-93 appears to be anchored in such a way as to optimize electrostatic interactions with developing negative charge at C-6 of the pyrimidine ring, and to donate the proton that replaces the carboxylate group at C-6 of the product. In addition, H-bonds from the active site to O-2 and O-4 help to delocalize negative charge in the transition state. Interactions between the enzyme and the phosphoribosyl group anchor the pyrimidine within the active site, helping to explain the phosphoribosyl group's remarkably large contribution to catalysis despite its distance from the site of decarboxylation.
About this Structure
1DQX is a Single protein structure of sequence from Saccharomyces cerevisiae with as ligand. Active as Orotidine-5'-phosphate decarboxylase, with EC number 4.1.1.23 Full crystallographic information is available from OCA.
Reference
Anatomy of a proficient enzyme: the structure of orotidine 5'-monophosphate decarboxylase in the presence and absence of a potential transition state analog., Miller BG, Hassell AM, Wolfenden R, Milburn MV, Short SA, Proc Natl Acad Sci U S A. 2000 Feb 29;97(5):2011-6. PMID:10681417
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