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1h6m
From Proteopedia
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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 ... [(full description)]
About this Structure
1H6M is a [Single protein] structure of sequence from [Gallus gallus] with NA as [ligand]. Active as [[1]], with EC number [3.2.1.17]. 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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