2pb1: Difference between revisions
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'''Exo-B-(1,3)-Glucanase from Candida Albicans in complex with unhydrolysed and covalently linked 2,4-dinitrophenyl-2-deoxy-2-fluoro-B-D-glucopyranoside at 1.9 A''' | {{Structure | ||
|PDB= 2pb1 |SIZE=350|CAPTION= <scene name='initialview01'>2pb1</scene>, resolution 1.900Å | |||
|SITE= | |||
|LIGAND= <scene name='pdbligand=G2F:2-DEOXY-2FLUORO-GLUCOSE'>G2F</scene> and <scene name='pdbligand=NFG:2,4-DINITROPHENYL 2-DEOXY-2-FLUORO-BETA-D-GLUCOPYRANOSIDE'>NFG</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] | |||
|GENE= EXG ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=5476 Candida albicans]) | |||
}} | |||
'''Exo-B-(1,3)-Glucanase from Candida Albicans in complex with unhydrolysed and covalently linked 2,4-dinitrophenyl-2-deoxy-2-fluoro-B-D-glucopyranoside at 1.9 A''' | |||
==Overview== | ==Overview== | ||
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==About this Structure== | ==About this Structure== | ||
2PB1 is a [ | 2PB1 is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Candida_albicans Candida albicans]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2PB1 OCA]. | ||
==Reference== | ==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:[http:// | 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:[http://www.ncbi.nlm.nih.gov/pubmed/10610795 10610795] | ||
[[Category: Candida albicans]] | [[Category: Candida albicans]] | ||
[[Category: Glucan 1,3-beta-glucosidase]] | [[Category: Glucan 1,3-beta-glucosidase]] | ||
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[[Category: G2F]] | [[Category: G2F]] | ||
[[Category: NFG]] | [[Category: NFG]] | ||
[[Category: candida | [[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 Thu | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Mar 20 18:11:01 2008'' | ||
Revision as of 16:11, 20 March 2008
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| 2pb1, resolution 1.900Å | |||||||||||||
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| Ligands: | G2F and NFG | ||||||||||||
| Gene: | EXG (Candida albicans) | ||||||||||||
| Activity: | Glucan 1,3-beta-glucosidase, with EC number 3.2.1.58 | ||||||||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||||||||
Exo-B-(1,3)-Glucanase from Candida Albicans in complex with unhydrolysed and covalently linked 2,4-dinitrophenyl-2-deoxy-2-fluoro-B-D-glucopyranoside at 1.9 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
2PB1 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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