2ahg: Difference between revisions
No edit summary |
No edit summary |
||
| Line 1: | Line 1: | ||
[[Image:2ahg.gif|left|200px]] | [[Image:2ahg.gif|left|200px]] | ||
'''Unsaturated glucuronyl hydrolase mutant D88N with dGlcA-GalNAc''' | {{Structure | ||
|PDB= 2ahg |SIZE=350|CAPTION= <scene name='initialview01'>2ahg</scene>, resolution 1.90Å | |||
|SITE= | |||
|LIGAND= <scene name='pdbligand=UCD:(4S,5R,6R)-6-((2R,3R,4R,5R,6R)-3-ACETAMIDO-2,5-DIHYDROXY-6-(HYDROXYMETHYL)-TETRAHYDRO-2H-PYRAN-4-YLOXY)-4,5-DIHYDROXY-5,6-DIHYDRO-4H-PYRAN-2-CARBOXYLIC ACID'>UCD</scene> | |||
|ACTIVITY= | |||
|GENE= | |||
}} | |||
'''Unsaturated glucuronyl hydrolase mutant D88N with dGlcA-GalNAc''' | |||
==Overview== | ==Overview== | ||
| Line 7: | Line 16: | ||
==About this Structure== | ==About this Structure== | ||
2AHG is a [ | 2AHG is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Bacillus_sp. Bacillus sp.]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2AHG OCA]. | ||
==Reference== | ==Reference== | ||
Crystal structure of unsaturated glucuronyl hydrolase complexed with substrate: molecular insights into its catalytic reaction mechanism., Itoh T, Hashimoto W, Mikami B, Murata K, J Biol Chem. 2006 Oct 6;281(40):29807-16. Epub 2006 Aug 7. PMID:[http:// | Crystal structure of unsaturated glucuronyl hydrolase complexed with substrate: molecular insights into its catalytic reaction mechanism., Itoh T, Hashimoto W, Mikami B, Murata K, J Biol Chem. 2006 Oct 6;281(40):29807-16. Epub 2006 Aug 7. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/16893885 16893885] | ||
[[Category: Bacillus sp.]] | [[Category: Bacillus sp.]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| Line 22: | Line 31: | ||
[[Category: glycoside hydrolase family 88]] | [[Category: glycoside hydrolase family 88]] | ||
''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 15:49:43 2008'' | ||
Revision as of 13:49, 20 March 2008
| |||||||||||||
| 2ahg, resolution 1.90Å | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Ligands: | UCD | ||||||||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||||||||
Unsaturated glucuronyl hydrolase mutant D88N with dGlcA-GalNAc
Overview
Unsaturated glucuronyl hydrolase (UGL), which is a member of glycoside hydrolase family GH-88, is a bacterial enzyme that degrades mammalian glycosaminoglycans and bacterial biofilms. The enzyme, which acts on unsaturated oligosaccharides with an alpha-glycoside bond produced by microbial polysaccharide lyases responsible for bacterial invasion of host cells, was believed to release 4-deoxy-l-threo-5-hexosulose-uronate (unsaturated glucuronic acid, or DeltaGlcA) and saccharide with a new nonreducing terminus by hydrolyzing the glycosidic bond. We detail the crystal structures of wild-type inactive mutant UGL of Bacillus sp. GL1 and its complex with a substrate (unsaturated chondroitin disaccharide), identify active site residues, and postulate a reaction mechanism catalyzed by UGL that triggers the hydration of the vinyl ether group in DeltaGlcA, based on the structural analysis of the enzyme-substrate complex and biochemical analysis. The proposed catalytic mechanism of UGL is a novel case among known glycosidases. Under the proposed mechanism, Asp-149 acts as a general acid and base catalyst to protonate the DeltaGlcA C4 atom and to deprotonate the water molecule. The deprotonated water molecule attacks the DeltaGlcA C5 atom to yield unstable hemiketal; this is followed by spontaneous conversion to an aldehyde (4-deoxy-l-threo-5-hexosulose-uronate) and saccharide through hemiacetal formation and cleavage of the glycosidic bond. UGL is the first clarified alpha(6)/alpha(6)-barrel enzyme using aspartic acid as the general acid/base catalyst.
About this Structure
2AHG is a Single protein structure of sequence from Bacillus sp.. Full crystallographic information is available from OCA.
Reference
Crystal structure of unsaturated glucuronyl hydrolase complexed with substrate: molecular insights into its catalytic reaction mechanism., Itoh T, Hashimoto W, Mikami B, Murata K, J Biol Chem. 2006 Oct 6;281(40):29807-16. Epub 2006 Aug 7. PMID:16893885
Page seeded by OCA on Thu Mar 20 15:49:43 2008
