1h6m
From Proteopedia
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|PDB= 1h6m |SIZE=350|CAPTION= <scene name='initialview01'>1h6m</scene>, resolution 1.64Å | |PDB= 1h6m |SIZE=350|CAPTION= <scene name='initialview01'>1h6m</scene>, resolution 1.64Å | ||
|SITE= <scene name='pdbsite=NA:Na+Binding+Site+For+Chain+A'>NA</scene>, <scene name='pdbsite=NAG:Nag+Binding+Site+For+Chain+A'>NAG</scene> and <scene name='pdbsite=NUC:The+Covalent+Intermediate+Is+Linked+To+The+Enzynmatic+Nu+...'>NUC</scene> | |SITE= <scene name='pdbsite=NA:Na+Binding+Site+For+Chain+A'>NA</scene>, <scene name='pdbsite=NAG:Nag+Binding+Site+For+Chain+A'>NAG</scene> and <scene name='pdbsite=NUC:The+Covalent+Intermediate+Is+Linked+To+The+Enzynmatic+Nu+...'>NUC</scene> | ||
| - | |LIGAND= <scene name='pdbligand=NA:SODIUM ION'>NA</scene> | + | |LIGAND= <scene name='pdbligand=G2F:2-DEOXY-2FLUORO-GLUCOSE'>G2F</scene>, <scene name='pdbligand=NA:SODIUM+ION'>NA</scene>, <scene name='pdbligand=NAG:N-ACETYL-D-GLUCOSAMINE'>NAG</scene> |
| - | |ACTIVITY= [http://en.wikipedia.org/wiki/Lysozyme Lysozyme], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.2.1.17 3.2.1.17] | + | |ACTIVITY= <span class='plainlinks'>[http://en.wikipedia.org/wiki/Lysozyme Lysozyme], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.2.1.17 3.2.1.17] </span> |
|GENE= | |GENE= | ||
| + | |DOMAIN= | ||
| + | |RELATEDENTRY= | ||
| + | |RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1h6m FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1h6m OCA], [http://www.ebi.ac.uk/pdbsum/1h6m PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1h6m RCSB]</span> | ||
}} | }} | ||
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[[Category: Vocadlo, D J.]] | [[Category: Vocadlo, D J.]] | ||
[[Category: Withers, S G.]] | [[Category: Withers, S G.]] | ||
| - | [[Category: NA]] | ||
[[Category: covalent intermediate]] | [[Category: covalent intermediate]] | ||
[[Category: glycoside hydrolase]] | [[Category: glycoside hydrolase]] | ||
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[[Category: mechanism]] | [[Category: mechanism]] | ||
| - | ''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 20:58:53 2008'' |
Revision as of 17:58, 30 March 2008
| |||||||
| , resolution 1.64Å | |||||||
|---|---|---|---|---|---|---|---|
| Sites: | , and | ||||||
| Ligands: | , , | ||||||
| Activity: | Lysozyme, with EC number 3.2.1.17 | ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
COVALENT GLYCOSYL-ENZYME INTERMEDIATE OF HEN EGG WHITE LYSOZYME
Overview
Hen egg-white lysozyme (HEWL) was the first enzyme to have its three-dimensional structure determined by X-ray diffraction techniques. A catalytic mechanism, featuring a long-lived oxocarbenium-ion intermediate, was proposed on the basis of model-building studies. The 'Phillips' mechanism is widely held as the paradigm for the catalytic mechanism of beta-glycosidases that cleave glycosidic linkages with net retention of configuration of the anomeric centre. Studies with other retaining beta-glycosidases, however, provide strong evidence pointing to a common mechanism for these enzymes that involves a covalent glycosyl-enzyme intermediate, as previously postulated. Here we show, in three different cases using electrospray ionization mass spectrometry, a catalytically competent covalent glycosyl-enzyme intermediate during the catalytic cycle of HEWL. We also show the three-dimensional structure of this intermediate as determined by X-ray diffraction. We formulate a general catalytic mechanism for all retaining beta-glycosidases that includes substrate distortion, formation of a covalent intermediate, and the electrophilic migration of C1 along the reaction coordinate.
About this Structure
1H6M is a Single protein structure of sequence from Gallus gallus. Full crystallographic information is available from OCA.
Reference
Catalysis by hen egg-white lysozyme proceeds via a covalent intermediate., Vocadlo DJ, Davies GJ, Laine R, Withers SG, Nature. 2001 Aug 23;412(6849):835-8. PMID:11518970
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