2e3d
From Proteopedia
(New page: 200px<br /><applet load="2e3d" size="450" color="white" frame="true" align="right" spinBox="true" caption="2e3d, resolution 1.95Å" /> '''Crystal structure of...) |
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- | [[Image:2e3d.jpg|left|200px]]<br /><applet load="2e3d" size=" | + | [[Image:2e3d.jpg|left|200px]]<br /><applet load="2e3d" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="2e3d, resolution 1.95Å" /> | caption="2e3d, resolution 1.95Å" /> | ||
'''Crystal structure of E. coli glucose-1-phosphate uridylyltransferase'''<br /> | '''Crystal structure of E. coli glucose-1-phosphate uridylyltransferase'''<br /> | ||
==Overview== | ==Overview== | ||
- | Glucose-1-phosphate uridylyltransferase, also referred to as UDP-glucose | + | Glucose-1-phosphate uridylyltransferase, also referred to as UDP-glucose pyrophosphorylase or UGPase, catalyzes the formation of UDP-glucose from glucose-1-phosphate and UTP. Not surprisingly, given the central role of UDP-glucose in glycogen synthesis and in the production of glycolipids, glycoproteins, and proteoglycans, the enzyme is ubiquitous in nature. Interestingly, however, the prokaryotic and eukaryotic forms of the enzyme are unrelated in amino acid sequence and structure. Here we describe the cloning and structural analysis to 1.9 A resolution of the UGPase from Escherichia coli. The protein is a tetramer with 222 point group symmetry. Each subunit of the tetramer is dominated by an eight-stranded mixed beta-sheet. There are two additional layers of beta-sheet (two and three strands) and 10 alpha-helices. The overall fold of the molecule is remarkably similar to that observed for glucose-1-phosphate thymidylyltransferase in complex with its product, dTDP-glucose. On the basis of this similarity, a UDP-glucose moiety has been positioned into the active site of UGPase. This protein/product model predicts that the side chains of Gln 109 and Asp 137, respectively, serve to anchor the uracil ring and the ribose of UDP-glucose to the protein. The beta-phosphoryl group of the product is predicted to lie within hydrogen bonding distance to the epsilon-nitrogen of Lys 202 whereas the carboxylate group of Glu 201 is predicted to bridge the 2'- and 3'-hydroxyl groups of the glucosyl moiety. Details concerning the overall structure of UGPase and a comparison with glucose-1-phosphate thymidylyltransferase are presented. |
==About this Structure== | ==About this Structure== | ||
- | 2E3D is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Active as [http://en.wikipedia.org/wiki/UTP--glucose-1-phosphate_uridylyltransferase UTP--glucose-1-phosphate uridylyltransferase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.7.7.9 2.7.7.9] Full crystallographic information is available from [http:// | + | 2E3D is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Active as [http://en.wikipedia.org/wiki/UTP--glucose-1-phosphate_uridylyltransferase UTP--glucose-1-phosphate uridylyltransferase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.7.7.9 2.7.7.9] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2E3D OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: UTP--glucose-1-phosphate uridylyltransferase]] | [[Category: UTP--glucose-1-phosphate uridylyltransferase]] | ||
- | [[Category: Holden, H | + | [[Category: Holden, H M.]] |
- | [[Category: Thoden, J | + | [[Category: Thoden, J B.]] |
[[Category: carbohydrate]] | [[Category: carbohydrate]] | ||
[[Category: pyrophosphorylase]] | [[Category: pyrophosphorylase]] | ||
[[Category: udp-glucose]] | [[Category: udp-glucose]] | ||
- | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 17:05:35 2008'' |
Revision as of 15:05, 21 February 2008
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Crystal structure of E. coli glucose-1-phosphate uridylyltransferase
Overview
Glucose-1-phosphate uridylyltransferase, also referred to as UDP-glucose pyrophosphorylase or UGPase, catalyzes the formation of UDP-glucose from glucose-1-phosphate and UTP. Not surprisingly, given the central role of UDP-glucose in glycogen synthesis and in the production of glycolipids, glycoproteins, and proteoglycans, the enzyme is ubiquitous in nature. Interestingly, however, the prokaryotic and eukaryotic forms of the enzyme are unrelated in amino acid sequence and structure. Here we describe the cloning and structural analysis to 1.9 A resolution of the UGPase from Escherichia coli. The protein is a tetramer with 222 point group symmetry. Each subunit of the tetramer is dominated by an eight-stranded mixed beta-sheet. There are two additional layers of beta-sheet (two and three strands) and 10 alpha-helices. The overall fold of the molecule is remarkably similar to that observed for glucose-1-phosphate thymidylyltransferase in complex with its product, dTDP-glucose. On the basis of this similarity, a UDP-glucose moiety has been positioned into the active site of UGPase. This protein/product model predicts that the side chains of Gln 109 and Asp 137, respectively, serve to anchor the uracil ring and the ribose of UDP-glucose to the protein. The beta-phosphoryl group of the product is predicted to lie within hydrogen bonding distance to the epsilon-nitrogen of Lys 202 whereas the carboxylate group of Glu 201 is predicted to bridge the 2'- and 3'-hydroxyl groups of the glucosyl moiety. Details concerning the overall structure of UGPase and a comparison with glucose-1-phosphate thymidylyltransferase are presented.
About this Structure
2E3D is a Single protein structure of sequence from Escherichia coli. Active as UTP--glucose-1-phosphate uridylyltransferase, with EC number 2.7.7.9 Full crystallographic information is available from OCA.
Reference
The molecular architecture of glucose-1-phosphate uridylyltransferase., Thoden JB, Holden HM, Protein Sci. 2007 Mar;16(3):432-40. PMID:17322528
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