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1h6m
From Proteopedia
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| - | [[Image:1h6m.gif|left|200px]] | + | [[Image:1h6m.gif|left|200px]] |
| - | + | ||
| - | '''COVALENT GLYCOSYL-ENZYME INTERMEDIATE OF HEN EGG WHITE LYSOZYME''' | + | {{Structure |
| + | |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> | ||
| + | |LIGAND= <scene name='pdbligand=NA:SODIUM ION'>NA</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] | ||
| + | |GENE= | ||
| + | }} | ||
| + | |||
| + | '''COVALENT GLYCOSYL-ENZYME INTERMEDIATE OF HEN EGG WHITE LYSOZYME''' | ||
| + | |||
==Overview== | ==Overview== | ||
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==About this Structure== | ==About this Structure== | ||
| - | 1H6M is a [ | + | 1H6M is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Gallus_gallus Gallus gallus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1H6M OCA]. |
==Reference== | ==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:[http:// | + | 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:[http://www.ncbi.nlm.nih.gov/pubmed/11518970 11518970] |
[[Category: Gallus gallus]] | [[Category: Gallus gallus]] | ||
[[Category: Lysozyme]] | [[Category: Lysozyme]] | ||
| Line 24: | Line 33: | ||
[[Category: mechanism]] | [[Category: mechanism]] | ||
| - | ''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 11:32:57 2008'' |
Revision as of 09:32, 20 March 2008
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| , resolution 1.64Å | |||||||
|---|---|---|---|---|---|---|---|
| Sites: | , and | ||||||
| Ligands: | |||||||
| Activity: | Lysozyme, with EC number 3.2.1.17 | ||||||
| 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
Page seeded by OCA on Thu Mar 20 11:32:57 2008
