1hzj
From Proteopedia
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| - | [[Image:1hzj.gif|left|200px]] | + | [[Image:1hzj.gif|left|200px]] |
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| - | '''HUMAN UDP-GALACTOSE 4-EPIMERASE: ACCOMMODATION OF UDP-N-ACETYLGLUCOSAMINE WITHIN THE ACTIVE SITE''' | + | {{Structure |
| + | |PDB= 1hzj |SIZE=350|CAPTION= <scene name='initialview01'>1hzj</scene>, resolution 1.5Å | ||
| + | |SITE= | ||
| + | |LIGAND= <scene name='pdbligand=CL:CHLORIDE+ION'>CL</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=NAD:NICOTINAMIDE-ADENINE-DINUCLEOTIDE'>NAD</scene> and <scene name='pdbligand=UD1:URIDINE-DIPHOSPHATE-N-ACETYLGLUCOSAMINE'>UD1</scene> | ||
| + | |ACTIVITY= [http://en.wikipedia.org/wiki/UDP-glucose_4-epimerase UDP-glucose 4-epimerase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=5.1.3.2 5.1.3.2] | ||
| + | |GENE= | ||
| + | }} | ||
| + | |||
| + | '''HUMAN UDP-GALACTOSE 4-EPIMERASE: ACCOMMODATION OF UDP-N-ACETYLGLUCOSAMINE WITHIN THE ACTIVE SITE''' | ||
| + | |||
==Overview== | ==Overview== | ||
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==About this Structure== | ==About this Structure== | ||
| - | 1HZJ is a [ | + | 1HZJ is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1HZJ OCA]. |
==Reference== | ==Reference== | ||
| - | Human UDP-galactose 4-epimerase. Accommodation of UDP-N-acetylglucosamine within the active site., Thoden JB, Wohlers TM, Fridovich-Keil JL, Holden HM, J Biol Chem. 2001 May 4;276(18):15131-6. Epub 2001 Jan 26. PMID:[http:// | + | Human UDP-galactose 4-epimerase. Accommodation of UDP-N-acetylglucosamine within the active site., Thoden JB, Wohlers TM, Fridovich-Keil JL, Holden HM, J Biol Chem. 2001 May 4;276(18):15131-6. Epub 2001 Jan 26. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/11279032 11279032] |
[[Category: Homo sapiens]] | [[Category: Homo sapiens]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
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[[Category: short-chain dehydrogenase]] | [[Category: short-chain dehydrogenase]] | ||
| - | ''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 11:43:43 2008'' |
Revision as of 09:43, 20 March 2008
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| , resolution 1.5Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | , , and | ||||||
| Activity: | UDP-glucose 4-epimerase, with EC number 5.1.3.2 | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
HUMAN UDP-GALACTOSE 4-EPIMERASE: ACCOMMODATION OF UDP-N-ACETYLGLUCOSAMINE WITHIN THE ACTIVE SITE
Contents |
Overview
UDP-galactose 4-epimerase catalyzes the interconversion of UDP-galactose and UDP-glucose during normal galactose metabolism. One of the key structural features in the proposed reaction mechanism for the enzyme is the rotation of a 4'-ketopyranose intermediate within the active site pocket. Recently, the three-dimensional structure of the human enzyme with bound NADH and UDP-glucose was determined. Unlike that observed for the protein isolated from Escherichia coli, the human enzyme can also turn over UDP-GlcNAc to UDP-GalNAc and vice versa. Here we describe the three-dimensional structure of human epimerase complexed with NADH and UDP-GlcNAc. To accommodate the additional N-acetyl group at the C2 position of the sugar, the side chain of Asn-207 rotates toward the interior of the protein and interacts with Glu-199. Strikingly, in the human enzyme, the structural equivalent of Tyr-299 in the E. coli protein is replaced with a cysteine residue (Cys-307) and the active site volume for the human protein is calculated to be approximately 15% larger than that observed for the bacterial epimerase. This combination of a larger active site cavity and amino acid residue replacement most likely accounts for the inability of the E. coli enzyme to interconvert UDP-GlcNAc and UDP-GalNAc.
Disease
Known disease associated with this structure: Galactose epimerase deficiency OMIM:[606953]
About this Structure
1HZJ is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.
Reference
Human UDP-galactose 4-epimerase. Accommodation of UDP-N-acetylglucosamine within the active site., Thoden JB, Wohlers TM, Fridovich-Keil JL, Holden HM, J Biol Chem. 2001 May 4;276(18):15131-6. Epub 2001 Jan 26. PMID:11279032
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