1eqc
From Proteopedia
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|SITE= | |SITE= | ||
|LIGAND= <scene name='pdbligand=CTS:CASTANOSPERMINE'>CTS</scene> | |LIGAND= <scene name='pdbligand=CTS:CASTANOSPERMINE'>CTS</scene> | ||
- | |ACTIVITY= [http://en.wikipedia.org/wiki/Glucan_1,3-beta-glucosidase Glucan 1,3-beta-glucosidase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.2.1.58 3.2.1.58] | + | |ACTIVITY= <span class='plainlinks'>[http://en.wikipedia.org/wiki/Glucan_1,3-beta-glucosidase Glucan 1,3-beta-glucosidase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.2.1.58 3.2.1.58] </span> |
|GENE= | |GENE= | ||
+ | |DOMAIN= | ||
+ | |RELATEDENTRY=[[1cz1|1CZ1]] | ||
+ | |RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1eqc FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1eqc OCA], [http://www.ebi.ac.uk/pdbsum/1eqc PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1eqc RCSB]</span> | ||
}} | }} | ||
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[[Category: Murshudov, G.]] | [[Category: Murshudov, G.]] | ||
[[Category: Sullivan, P A.]] | [[Category: Sullivan, P A.]] | ||
- | [[Category: CTS]] | ||
[[Category: candida albican]] | [[Category: candida albican]] | ||
[[Category: exo-glucanase]] | [[Category: exo-glucanase]] | ||
[[Category: mechanism-based inhibitor]] | [[Category: mechanism-based inhibitor]] | ||
- | ''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 20:07:42 2008'' |
Revision as of 17:07, 30 March 2008
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, resolution 1.85Å | |||||||
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Ligands: | |||||||
Activity: | Glucan 1,3-beta-glucosidase, with EC number 3.2.1.58 | ||||||
Related: | 1CZ1
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Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
Coordinates: | save as pdb, mmCIF, xml |
EXO-B-(1,3)-GLUCANASE FROM CANDIDA ALBICANS IN COMPLEX WITH CASTANOSPERMINE AT 1.85 A
Overview
A group of fungal exo-beta-(1,3)-glucanases, including that from the human pathogen Candida albicans (Exg), belong to glycosyl hydrolase family 5 that also includes many bacterial cellulases (endo-beta-1, 4-glucanases). Family members, despite wide sequence variations, share a common mechanism and are characterised by possessing eight invariant residues making up the active site. These include two glutamate residues acting as nucleophile and acid/base, respectively. Exg is an abundant secreted enzyme possessing both hydrolase and transferase activity consistent with a role in cell wall glucan metabolism and possibly morphogenesis. The structures of Exg in both free and inhibited forms have been determined to 1.9 A resolution. A distorted (beta/alpha)8 barrel structure accommodates an active site which is located within a deep pocket, formed when extended loop regions close off a cellulase-like groove. Structural analysis of a covalently bound mechanism-based inhibitor (2-fluoroglucosylpyranoside) and of a transition-state analogue (castanospermine) has identified the binding interactions at the -1 glucose binding site. In particular the carboxylate of Glu27 serves a dominant hydrogen-bonding role. Access by a 1,3-glucan chain to the pocket in Exg can be understood in terms of a change in conformation of the terminal glucose residue from chair to twisted boat. The geometry of the pocket is not, however, well suited for cleavage of 1,4-glycosidic linkages. A second glucose site was identified at the entrance to the pocket, sandwiched between two antiparallel phenylalanine side-chains. This aromatic entrance-way must not only direct substrate into the pocket but also may act as a clamp for an acceptor molecule participating in the transfer reaction.
About this Structure
1EQC is a Single protein structure of sequence from Candida albicans. Full crystallographic information is available from OCA.
Reference
The structure of the exo-beta-(1,3)-glucanase from Candida albicans in native and bound forms: relationship between a pocket and groove in family 5 glycosyl hydrolases., Cutfield SM, Davies GJ, Murshudov G, Anderson BF, Moody PC, Sullivan PA, Cutfield JF, J Mol Biol. 1999 Dec 3;294(3):771-83. PMID:10610795
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