This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.


Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.


2ahg

From Proteopedia

(Difference between revisions)
Jump to: navigation, search
Line 1: Line 1:
-
[[Image:2ahg.gif|left|200px]]
+
{{Seed}}
 +
[[Image:2ahg.png|left|200px]]
<!--
<!--
Line 9: Line 10:
{{STRUCTURE_2ahg| PDB=2ahg | SCENE= }}
{{STRUCTURE_2ahg| PDB=2ahg | SCENE= }}
-
'''Unsaturated glucuronyl hydrolase mutant D88N with dGlcA-GalNAc'''
+
===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.
+
The line below this paragraph, {{ABSTRACT_PUBMED_16893885}}, adds the Publication Abstract to the page
 +
(as it appears on PubMed at http://www.pubmed.gov), where 16893885 is the PubMed ID number.
 +
-->
 +
{{ABSTRACT_PUBMED_16893885}}
==About this Structure==
==About this Structure==
Line 29: Line 33:
[[Category: Complex with unsaturated chondroitin disaccharide]]
[[Category: Complex with unsaturated chondroitin disaccharide]]
[[Category: Glycoside hydrolase family 88]]
[[Category: Glycoside hydrolase family 88]]
-
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sat May 3 19:03:10 2008''
+
 
 +
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Mon Jul 28 11:23:07 2008''

Revision as of 08:23, 28 July 2008

Template:STRUCTURE 2ahg

Unsaturated glucuronyl hydrolase mutant D88N with dGlcA-GalNAc

Template:ABSTRACT PUBMED 16893885

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 Mon Jul 28 11:23:07 2008

Proteopedia Page Contributors and Editors (what is this?)

OCA

Personal tools