1jez
From Proteopedia
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| - | [[Image:1jez.jpg|left|200px]] | + | [[Image:1jez.jpg|left|200px]] |
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| - | '''THE STRUCTURE OF XYLOSE REDUCTASE, A DIMERIC ALDO-KETO REDUCTASE FROM CANDIDA TENUIS''' | + | {{Structure |
| + | |PDB= 1jez |SIZE=350|CAPTION= <scene name='initialview01'>1jez</scene>, resolution 2.20Å | ||
| + | |SITE= | ||
| + | |LIGAND= | ||
| + | |ACTIVITY= [http://en.wikipedia.org/wiki/Aldehyde_reductase Aldehyde reductase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.1.1.21 1.1.1.21] | ||
| + | |GENE= XYLR ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=45596 Candida tenuis]) | ||
| + | }} | ||
| + | |||
| + | '''THE STRUCTURE OF XYLOSE REDUCTASE, A DIMERIC ALDO-KETO REDUCTASE FROM CANDIDA TENUIS''' | ||
| + | |||
==Overview== | ==Overview== | ||
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==About this Structure== | ==About this Structure== | ||
| - | 1JEZ is a [ | + | 1JEZ is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Candida_tenuis Candida tenuis]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1JEZ OCA]. |
==Reference== | ==Reference== | ||
| - | The structure of apo and holo forms of xylose reductase, a dimeric aldo-keto reductase from Candida tenuis., Kavanagh KL, Klimacek M, Nidetzky B, Wilson DK, Biochemistry. 2002 Jul 16;41(28):8785-95. PMID:[http:// | + | The structure of apo and holo forms of xylose reductase, a dimeric aldo-keto reductase from Candida tenuis., Kavanagh KL, Klimacek M, Nidetzky B, Wilson DK, Biochemistry. 2002 Jul 16;41(28):8785-95. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/12102621 12102621] |
[[Category: Aldehyde reductase]] | [[Category: Aldehyde reductase]] | ||
[[Category: Candida tenuis]] | [[Category: Candida tenuis]] | ||
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[[Category: tim barrel]] | [[Category: tim barrel]] | ||
| - | ''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 12:02:32 2008'' |
Revision as of 10:02, 20 March 2008
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| , resolution 2.20Å | |||||||
|---|---|---|---|---|---|---|---|
| Gene: | XYLR (Candida tenuis) | ||||||
| Activity: | Aldehyde reductase, with EC number 1.1.1.21 | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
THE STRUCTURE OF XYLOSE REDUCTASE, A DIMERIC ALDO-KETO REDUCTASE FROM CANDIDA TENUIS
Overview
Xylose reductase is a homodimeric oxidoreductase dependent on NADPH or NADH and belongs to the largely monomeric aldo-keto reductase superfamily of proteins. It catalyzes the first step in the assimilation of xylose, an aldose found to be a major constituent monosaccharide of renewable plant hemicellulosic material, into yeast metabolic pathways. It does this by reducing open chain xylose to xylitol, which is reoxidized to xylulose by xylitol dehydrogenase and metabolically integrated via the pentose phosphate pathway. No structure has yet been determined for a xylose reductase, a dimeric aldo-keto reductase or a family 2 aldo-keto reductase. The structures of the Candida tenuis xylose reductase apo- and holoenzyme, which crystallize in spacegroup C2 with different unit cells, have been determined to 2.2 A resolution and an R-factor of 17.9 and 20.8%, respectively. Residues responsible for mediating the novel dimeric interface include Asp-178, Arg-181, Lys-202, Phe-206, Trp-313, and Pro-319. Alignments with other superfamily members indicate that these interactions are conserved in other dimeric xylose reductases but not throughout the remainder of the oligomeric aldo-keto reductases, predicting alternate modes of oligomerization for other families. An arrangement of side chains in a catalytic triad shows that Tyr-52 has a conserved function as a general acid. The loop that folds over the NAD(P)H cosubstrate is disordered in the apo form but becomes ordered upon cosubstrate binding. A slow conformational isomerization of this loop probably accounts for the observed rate-limiting step involving release of cosubstrate. Xylose binding (K(m) = 87 mM) is mediated by interactions with a binding pocket that is more polar than a typical aldo-keto reductase. Modeling of xylose into the active site of the holoenzyme using ordered waters as a guide for sugar hydroxyls suggests a convincing mode of substrate binding.
About this Structure
1JEZ is a Single protein structure of sequence from Candida tenuis. Full crystallographic information is available from OCA.
Reference
The structure of apo and holo forms of xylose reductase, a dimeric aldo-keto reductase from Candida tenuis., Kavanagh KL, Klimacek M, Nidetzky B, Wilson DK, Biochemistry. 2002 Jul 16;41(28):8785-95. PMID:12102621
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