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1w8n
From Proteopedia
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[[Category: neuraminidase]] | [[Category: neuraminidase]] | ||
| - | ''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Tue Oct 30 | + | ''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Tue Oct 30 16:28:32 2007'' |
Revision as of 14:23, 30 October 2007
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CONTRIBUTION OF THE ACTIVE SITE ASPARTIC ACID TO CATALYSIS IN THE BACTERIAL NEURAMINIDASE FROM MICROMONOSPORA VIRIDIFACIENS.
Overview
A recombinant D92G mutant sialidase from Micromonospora viridifaciens has, been cloned, expressed and purified. Kinetic studies reveal that the, replacement of the conserved aspartic acid with glycine results in a, catalytically competent retaining sialidase that possesses significant, activity against activated substrates. The contribution of this aspartate, residue to the free energy of hydrolysis for natural substrates is greater, than 19 kJ/mol. The three dimensional structure of the D92G mutant shows, that the removal of aspartic acid 92 causes no significant re-arrangement, of the active site, and that an ordered water molecule substitutes for the, carboxylate group of D92.
About this Structure
1W8N is a [Single protein] structure of sequence from [Micromonospora viridifaciens] with GAL, NA and DAN as [ligands]. Active as [Exo-alpha-sialidase], with EC number [3.2.1.18]. Structure known Active Site: AC1. Full crystallographic information is available from [OCA].
Reference
Contribution of the active site aspartic acid to catalysis in the bacterial neuraminidase from Micromonospora viridifaciens., Watson JN, Newstead S, Dookhun V, Taylor G, Bennet AJ, FEBS Lett. 2004 Nov 5;577(1-2):265-9. PMID:15527797
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