1qh6
From Proteopedia
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| - | [[Image:1qh6.jpg|left|200px]] | + | [[Image:1qh6.jpg|left|200px]] |
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| - | '''CATALYSIS AND SPECIFICITY IN ENZYMATIC GLYCOSIDE HYDROLASES: A 2,5B CONFORMATION FOR THE GLYCOSYL-ENZYME INTERMIDIATE REVEALED BY THE STRUCTURE OF THE BACILLUS AGARADHAERENS FAMILY 11 XYLANASE''' | + | {{Structure |
| + | |PDB= 1qh6 |SIZE=350|CAPTION= <scene name='initialview01'>1qh6</scene>, resolution 2.00Å | ||
| + | |SITE= | ||
| + | |LIGAND= <scene name='pdbligand=FXP:1,2,-DEOXY-2-FLUORO-4-O-BETA-D-XYLOPYRANOSYL-BETA-D-XYLOPYRANOSE'>FXP</scene> | ||
| + | |ACTIVITY= [http://en.wikipedia.org/wiki/Endo-1,4-beta-xylanase Endo-1,4-beta-xylanase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.2.1.8 3.2.1.8] | ||
| + | |GENE= | ||
| + | }} | ||
| + | |||
| + | '''CATALYSIS AND SPECIFICITY IN ENZYMATIC GLYCOSIDE HYDROLASES: A 2,5B CONFORMATION FOR THE GLYCOSYL-ENZYME INTERMIDIATE REVEALED BY THE STRUCTURE OF THE BACILLUS AGARADHAERENS FAMILY 11 XYLANASE''' | ||
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==Overview== | ==Overview== | ||
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==About this Structure== | ==About this Structure== | ||
| - | 1QH6 is a [ | + | 1QH6 is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Bacillus_agaradhaerens Bacillus agaradhaerens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1QH6 OCA]. |
==Reference== | ==Reference== | ||
| - | Catalysis and specificity in enzymatic glycoside hydrolysis: a 2,5B conformation for the glycosyl-enzyme intermediate revealed by the structure of the Bacillus agaradhaerens family 11 xylanase., Sabini E, Sulzenbacher G, Dauter M, Dauter Z, Jorgensen PL, Schulein M, Dupont C, Davies GJ, Wilson KS, Chem Biol. 1999 Jul;6(7):483-92. PMID:[http:// | + | Catalysis and specificity in enzymatic glycoside hydrolysis: a 2,5B conformation for the glycosyl-enzyme intermediate revealed by the structure of the Bacillus agaradhaerens family 11 xylanase., Sabini E, Sulzenbacher G, Dauter M, Dauter Z, Jorgensen PL, Schulein M, Dupont C, Davies GJ, Wilson KS, Chem Biol. 1999 Jul;6(7):483-92. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/10381409 10381409] |
[[Category: Bacillus agaradhaerens]] | [[Category: Bacillus agaradhaerens]] | ||
[[Category: Endo-1,4-beta-xylanase]] | [[Category: Endo-1,4-beta-xylanase]] | ||
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[[Category: glycosyl hydrolase]] | [[Category: glycosyl hydrolase]] | ||
| - | ''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 13:37:23 2008'' |
Revision as of 11:37, 20 March 2008
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| , resolution 2.00Å | |||||||
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| Ligands: | |||||||
| Activity: | Endo-1,4-beta-xylanase, with EC number 3.2.1.8 | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
CATALYSIS AND SPECIFICITY IN ENZYMATIC GLYCOSIDE HYDROLASES: A 2,5B CONFORMATION FOR THE GLYCOSYL-ENZYME INTERMIDIATE REVEALED BY THE STRUCTURE OF THE BACILLUS AGARADHAERENS FAMILY 11 XYLANASE
Overview
BACKGROUND: The enzymatic hydrolysis of glycosides involves the formation and subsequent breakdown of a covalent glycosyl-enzyme intermediate via oxocarbenium-ion-like transition states. The covalent intermediate may be trapped on-enzyme using 2-fluoro-substituted glycosides, which provide details of the intermediate conformation and noncovalent interactions between enzyme and oligosaccharide. Xylanases are important in industrial applications - in the pulp and paper industry, pretreating wood with xylanases decreases the amount of chlorine-containing chemicals used. Xylanases are structurally similar to cellulases but differ in their specificity for xylose-based, versus glucose-based, substrates. RESULTS: The structure of the family 11 xylanase, Xyl11, from Bacillus agaradhaerens has been solved using X-ray crystallography in both native and xylobiosyl-enzyme intermediate forms at 1.78 A and 2.0 A resolution, respectively. The covalent glycosyl-enzyme intermediate has been trapped using a 2-fluoro-2-deoxy substrate with a good leaving group. Unlike covalent intermediate structures for glycoside hydrolases from other families, the covalent glycosyl-enzyme intermediate in family 11 adopts an unusual 2,5B conformation. CONCLUSIONS: The 2,5B conformation found for the alpha-linked xylobiosyl-enzyme intermediate of Xyl11, unlike the 4C1 chair conformation observed for other systems, is consistent with the stereochemical constraints required of the oxocarbenium-ion-like transition state. Comparison of the Xyl11 covalent glycosyl-enzyme intermediate with the equivalent structure for the related family 12 endoglucanase, CelB, from Streptomyces lividans reveals the likely determinants for substrate specificity in this clan of glycoside hydrolases.
About this Structure
1QH6 is a Single protein structure of sequence from Bacillus agaradhaerens. Full crystallographic information is available from OCA.
Reference
Catalysis and specificity in enzymatic glycoside hydrolysis: a 2,5B conformation for the glycosyl-enzyme intermediate revealed by the structure of the Bacillus agaradhaerens family 11 xylanase., Sabini E, Sulzenbacher G, Dauter M, Dauter Z, Jorgensen PL, Schulein M, Dupont C, Davies GJ, Wilson KS, Chem Biol. 1999 Jul;6(7):483-92. PMID:10381409
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