2gl9: Difference between revisions
No edit summary |
No edit summary |
||
| Line 1: | Line 1: | ||
[[Image:2gl9.gif|left|200px]] | [[Image:2gl9.gif|left|200px]] | ||
<!-- | |||
The line below this paragraph, containing "STRUCTURE_2gl9", creates the "Structure Box" on the page. | |||
You may change the PDB parameter (which sets the PDB file loaded into the applet) | |||
or the SCENE parameter (which sets the initial scene displayed when the page is loaded), | |||
or leave the SCENE parameter empty for the default display. | |||
| | --> | ||
| | {{STRUCTURE_2gl9| PDB=2gl9 | SCENE= }} | ||
}} | |||
'''Crystal Structure of Glycosylasparaginase-Substrate Complex''' | '''Crystal Structure of Glycosylasparaginase-Substrate Complex''' | ||
| Line 24: | Line 21: | ||
Crystallographic snapshot of a productive glycosylasparaginase-substrate complex., Wang Y, Guo HC, J Mol Biol. 2007 Feb 9;366(1):82-92. Epub 2006 Sep 26. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/17157318 17157318] | Crystallographic snapshot of a productive glycosylasparaginase-substrate complex., Wang Y, Guo HC, J Mol Biol. 2007 Feb 9;366(1):82-92. Epub 2006 Sep 26. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/17157318 17157318] | ||
[[Category: Elizabethkingia meningoseptica]] | [[Category: Elizabethkingia meningoseptica]] | ||
[[Category: Protein complex]] | [[Category: Protein complex]] | ||
[[Category: Guo, H C.]] | [[Category: Guo, H C.]] | ||
[[Category: Wang, Y.]] | [[Category: Wang, Y.]] | ||
[[Category: | [[Category: Catalytic mechanism]] | ||
[[Category: | [[Category: Crystal structure]] | ||
[[Category: | [[Category: Electron-pair transfer]] | ||
[[Category: | [[Category: Enzyme-acyl intermediate]] | ||
[[Category: | [[Category: Enzyme-substrate complex]] | ||
[[Category: | [[Category: Glycosylasparaginase]] | ||
[[Category: | [[Category: Ntn-hydrolase]] | ||
[[Category: | [[Category: Nucleophilic attack]] | ||
[[Category: | [[Category: Oxyanion hole]] | ||
[[Category: | [[Category: Proton-relay network]] | ||
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun May 4 05:13:46 2008'' | |||
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | |||
Revision as of 02:13, 4 May 2008
Crystal Structure of Glycosylasparaginase-Substrate Complex
Overview
Glycosylasparaginase (GA) plays an important role in asparagine-linked glycoprotein degradation. A deficiency in the activity of human GA leads to a lysosomal storage disease named aspartylglycosaminuria. GA belongs to a superfamily of N-terminal nucleophile hydrolases that autoproteolytically generate their mature enzymes from inactive single chain protein precursors. The side-chain of the newly exposed N-terminal residue then acts as a nucleophile during substrate hydrolysis. By taking advantage of mutant enzyme of Flavobacterium meningosepticum GA with reduced enzymatic activity, we have obtained a crystallographic snapshot of a productive complex with its substrate (NAcGlc-Asn), at 2.0 A resolution. This complex structure provided us an excellent model for the Michaelis complex to examine the specific contacts critical for substrate binding and catalysis. Substrate binding induces a conformational change near the active site of GA. To initiate catalysis, the side-chain of the N-terminal Thr152 is polarized by the free alpha-amino group on the same residue, mediated by the side-chain hydroxyl group of Thr170. Cleavage of the amide bond is then accomplished by a nucleophilic attack at the carbonyl carbon of the amide linkage in the substrate, leading to the formation of an acyl-enzyme intermediate through a negatively charged tetrahedral transition state.
About this Structure
2GL9 is a Protein complex structure of sequences from Elizabethkingia meningoseptica. Full crystallographic information is available from OCA.
Reference
Crystallographic snapshot of a productive glycosylasparaginase-substrate complex., Wang Y, Guo HC, J Mol Biol. 2007 Feb 9;366(1):82-92. Epub 2006 Sep 26. PMID:17157318 Page seeded by OCA on Sun May 4 05:13:46 2008
