1rkx
From Proteopedia
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|SITE= | |SITE= | ||
|LIGAND= <scene name='pdbligand=NAD:NICOTINAMIDE-ADENINE-DINUCLEOTIDE'>NAD</scene> | |LIGAND= <scene name='pdbligand=NAD:NICOTINAMIDE-ADENINE-DINUCLEOTIDE'>NAD</scene> | ||
| - | |ACTIVITY= [http://en.wikipedia.org/wiki/CDP-glucose_4,6-dehydratase CDP-glucose 4,6-dehydratase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=4.2.1.45 4.2.1.45] | + | |ACTIVITY= <span class='plainlinks'>[http://en.wikipedia.org/wiki/CDP-glucose_4,6-dehydratase CDP-glucose 4,6-dehydratase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=4.2.1.45 4.2.1.45] </span> |
|GENE= ascB ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=633 Yersinia pseudotuberculosis]) | |GENE= ascB ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=633 Yersinia pseudotuberculosis]) | ||
| + | |DOMAIN= | ||
| + | |RELATEDENTRY= | ||
| + | |RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1rkx FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1rkx OCA], [http://www.ebi.ac.uk/pdbsum/1rkx PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1rkx RCSB]</span> | ||
}} | }} | ||
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[[Category: Ringe, D.]] | [[Category: Ringe, D.]] | ||
[[Category: Vogan, E M.]] | [[Category: Vogan, E M.]] | ||
| - | [[Category: NAD]] | ||
[[Category: cdp glucose dehydratase]] | [[Category: cdp glucose dehydratase]] | ||
[[Category: dehydratase]] | [[Category: dehydratase]] | ||
[[Category: sdr]] | [[Category: sdr]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Mar 30 23:29:36 2008'' |
Revision as of 20:29, 30 March 2008
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| , resolution 1.80Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | |||||||
| Gene: | ascB (Yersinia pseudotuberculosis) | ||||||
| Activity: | CDP-glucose 4,6-dehydratase, with EC number 4.2.1.45 | ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
Crystal Structure at 1.8 Angstrom of CDP-D-glucose 4,6-dehydratase from Yersinia pseudotuberculosis
Overview
CDP-D-glucose 4,6-dehydratase catalyzes the conversion of CDP-D-glucose to CDP-4-keto-6-deoxyglucose in an NAD(+)-dependent manner. The product of this conversion is a building block for a variety of primary antigenic determinants in bacteria, possibly implicated directly in reactive arthritis. Here, we describe the solution of the high-resolution crystal structure of CDP-D-glucose 4,6-dehydratase from Yersinia pseudotuberculosis in the resting state. This structure represents the first CDP nucleotide utilizing dehydratase of the short-chain dehydrogenase/reductase (SDR) family to be determined, as well as the first tetrameric structure of the subfamily of SDR enzymes in which NAD(+) undergoes a full reaction cycle. On the basis of a comparison of this structure with structures of homologous enzymes, a chemical mechanism is proposed in which Tyr157 acts as the catalytic base, initiating hydride transfer by abstraction of the proton from the sugar 4'-hydroxyl. Concomitant with the removal of the proton from the 4'-hydroxyl oxygen, the sugar 4'-hydride is transferred to the B face of the NAD(+) cofactor, forming the reduced cofactor and a CDP-4-keto-d-glucose intermediate. A conserved Lys161 most likely acts to position the NAD(+) cofactor so that hydride transfer is favorable and/or to reduce the pK(a) of Tyr157. Following substrate oxidation, we propose that Lys134, acting as a base, would abstract the 5'-hydrogen of CDP-4-keto-D-glucose, priming the intermediate for the spontaneous loss of water. Finally, the resulting Delta(5,6)-glucoseen intermediate would be reduced suprafacially by the cofactor, and reprotonation at C-5' is likely mediated by Lys134.
About this Structure
1RKX is a Single protein structure of sequence from Yersinia pseudotuberculosis. Full crystallographic information is available from OCA.
Reference
Crystal structure at 1.8 A resolution of CDP-D-glucose 4,6-dehydratase from Yersinia pseudotuberculosis., Vogan EM, Bellamacina C, He X, Liu HW, Ringe D, Petsko GA, Biochemistry. 2004 Mar 23;43(11):3057-67. PMID:15023057
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