1ojk: Difference between revisions

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[[Image:1ojk.png|left|200px]]
==ANATOMY OF GLYCOSYNTHESIS: STRUCTURE AND KINETICS OF THE HUMICOLA INSOLENS CEL7BE197A AND E197S GLYCOSYNTHASE MUTANTS==
<StructureSection load='1ojk' size='340' side='right' caption='[[1ojk]], [[Resolution|resolution]] 1.50&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1ojk]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/Humicola_insolens Humicola insolens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1OJK OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1OJK FirstGlance]. <br>
</td></tr><tr><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=BGC:BETA-D-GLUCOSE'>BGC</scene>, <scene name='pdbligand=GLC:ALPHA-D-GLUCOSE'>GLC</scene>, <scene name='pdbligand=GOL:GLYCEROL'>GOL</scene>, <scene name='pdbligand=NAG:N-ACETYL-D-GLUCOSAMINE'>NAG</scene><br>
<tr><td class="sblockLbl"><b>[[Non-Standard_Residue|NonStd Res:]]</b></td><td class="sblockDat"><scene name='pdbligand=PCA:PYROGLUTAMIC+ACID'>PCA</scene></td></tr>
<tr><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[1a39|1a39]], [[1dym|1dym]], [[1oji|1oji]], [[1ojj|1ojj]], [[2a39|2a39]]</td></tr>
<tr><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Cellulase Cellulase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.2.1.4 3.2.1.4] </span></td></tr>
<tr><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1ojk FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1ojk OCA], [http://www.rcsb.org/pdb/explore.do?structureId=1ojk RCSB], [http://www.ebi.ac.uk/pdbsum/1ojk PDBsum]</span></td></tr>
<table>
== Evolutionary Conservation ==
[[Image:Consurf_key_small.gif|200px|right]]
Check<jmol>
  <jmolCheckbox>
    <scriptWhenChecked>select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/oj/1ojk_consurf.spt"</scriptWhenChecked>
    <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked>
    <text>to colour the structure by Evolutionary Conservation</text>
  </jmolCheckbox>
</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/chain_selection.php?pdb_ID=2ata ConSurf].
<div style="clear:both"></div>
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
The formation of glycoconjugates and oligosaccharides remains one of the most challenging chemical syntheses. Chemo-enzymatic routes using retaining glycosidases have been successfully harnessed but require tight kinetic or thermodynamic control. "Glycosynthases," specifically engineered glycosidases that catalyze the formation of glycosidic bonds from glycosyl donor and acceptor alcohol, are an emerging range of synthetic tools in which catalytic nucleophile mutants are harnessed together with glycosyl fluoride donors to generate powerful and versatile catalysts. Here we present the structural and kinetic dissection of the Humicola insolens Cel7B glycosynthases in which the nucleophile of the wild-type enzyme is mutated to alanine and serine (E197A and E197S). 3-D structures reveal the acceptor and donor subsites and the basis for substrate inhibition. Kinetic analysis shows that the E197S mutant is considerably more active than the corresponding alanine mutant due to a 40-fold increase in k(cat).


{{STRUCTURE_1ojk|  PDB=1ojk  |  SCENE=  }}
Anatomy of glycosynthesis: structure and kinetics of the Humicola insolens Cel7B E197A and E197S glycosynthase mutants.,Ducros VM, Tarling CA, Zechel DL, Brzozowski AM, Frandsen TP, von Ossowski I, Schulein M, Withers SG, Davies GJ Chem Biol. 2003 Jul;10(7):619-28. PMID:12890535<ref>PMID:12890535</ref>


===ANATOMY OF GLYCOSYNTHESIS: STRUCTURE AND KINETICS OF THE HUMICOLA INSOLENS CEL7BE197A AND E197S GLYCOSYNTHASE MUTANTS===
From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
 
</div>
{{ABSTRACT_PUBMED_12890535}}
 
==About this Structure==
[[1ojk]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/Humicola_insolens Humicola insolens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1OJK OCA].


==See Also==
==See Also==
*[[Glucanase|Glucanase]]
*[[Glucanase|Glucanase]]
 
== References ==
==Reference==
<references/>
<ref group="xtra">PMID:012890535</ref><references group="xtra"/>
__TOC__
</StructureSection>
[[Category: Cellulase]]
[[Category: Cellulase]]
[[Category: Humicola insolens]]
[[Category: Humicola insolens]]

Revision as of 21:26, 28 September 2014

ANATOMY OF GLYCOSYNTHESIS: STRUCTURE AND KINETICS OF THE HUMICOLA INSOLENS CEL7BE197A AND E197S GLYCOSYNTHASE MUTANTSANATOMY OF GLYCOSYNTHESIS: STRUCTURE AND KINETICS OF THE HUMICOLA INSOLENS CEL7BE197A AND E197S GLYCOSYNTHASE MUTANTS

Structural highlights

1ojk is a 2 chain structure with sequence from Humicola insolens. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Ligands:, , ,
NonStd Res:
Related:1a39, 1dym, 1oji, 1ojj, 2a39
Activity:Cellulase, with EC number 3.2.1.4
Resources:FirstGlance, OCA, RCSB, PDBsum

Evolutionary Conservation

Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.

Publication Abstract from PubMed

The formation of glycoconjugates and oligosaccharides remains one of the most challenging chemical syntheses. Chemo-enzymatic routes using retaining glycosidases have been successfully harnessed but require tight kinetic or thermodynamic control. "Glycosynthases," specifically engineered glycosidases that catalyze the formation of glycosidic bonds from glycosyl donor and acceptor alcohol, are an emerging range of synthetic tools in which catalytic nucleophile mutants are harnessed together with glycosyl fluoride donors to generate powerful and versatile catalysts. Here we present the structural and kinetic dissection of the Humicola insolens Cel7B glycosynthases in which the nucleophile of the wild-type enzyme is mutated to alanine and serine (E197A and E197S). 3-D structures reveal the acceptor and donor subsites and the basis for substrate inhibition. Kinetic analysis shows that the E197S mutant is considerably more active than the corresponding alanine mutant due to a 40-fold increase in k(cat).

Anatomy of glycosynthesis: structure and kinetics of the Humicola insolens Cel7B E197A and E197S glycosynthase mutants.,Ducros VM, Tarling CA, Zechel DL, Brzozowski AM, Frandsen TP, von Ossowski I, Schulein M, Withers SG, Davies GJ Chem Biol. 2003 Jul;10(7):619-28. PMID:12890535[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

See Also

References

  1. Ducros VM, Tarling CA, Zechel DL, Brzozowski AM, Frandsen TP, von Ossowski I, Schulein M, Withers SG, Davies GJ. Anatomy of glycosynthesis: structure and kinetics of the Humicola insolens Cel7B E197A and E197S glycosynthase mutants. Chem Biol. 2003 Jul;10(7):619-28. PMID:12890535

1ojk, resolution 1.50Å

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