1ob0: Difference between revisions
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== | ==Kinetic stabilization of Bacillus licheniformis alpha-amylase through introduction of hydrophobic residues at the surface== | ||
It is generally assumed that in proteins hydrophobic residues are not | <StructureSection load='1ob0' size='340' side='right'caption='[[1ob0]], [[Resolution|resolution]] 1.83Å' scene=''> | ||
== Structural highlights == | |||
<table><tr><td colspan='2'>[[1ob0]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Bacillus_licheniformis Bacillus licheniformis]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1OB0 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1OB0 FirstGlance]. <br> | |||
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 1.83Å</td></tr> | |||
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CA:CALCIUM+ION'>CA</scene>, <scene name='pdbligand=NA:SODIUM+ION'>NA</scene></td></tr> | |||
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=1ob0 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1ob0 OCA], [https://pdbe.org/1ob0 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1ob0 RCSB], [https://www.ebi.ac.uk/pdbsum/1ob0 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1ob0 ProSAT]</span></td></tr> | |||
</table> | |||
== Function == | |||
[https://www.uniprot.org/uniprot/AMY_BACLI AMY_BACLI] | |||
== 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/ob/1ob0_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/main_output.php?pdb_ID=1ob0 ConSurf]. | |||
<div style="clear:both"></div> | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
It is generally assumed that in proteins hydrophobic residues are not favorable at solvent-exposed sites, and that amino acid substitutions on the surface have little effect on protein thermostability. Contrary to these assumptions, we have identified hyperthermostable variants of Bacillus licheniformis alpha-amylase (BLA) that result from the incorporation of hydrophobic residues at the surface. Under highly destabilizing conditions, a variant combining five stabilizing mutations unfolds 32 times more slowly and at a temperature 13 degrees C higher than the wild-type. Crystal structure analysis at 1.7 A resolution suggests that stabilization is achieved through (a) extension of the concept of increased hydrophobic packing, usually applied to cavities, to surface indentations, (b) introduction of favorable aromatic-aromatic interactions on the surface, (c) specific stabilization of intrinsic metal binding sites, and (d) stabilization of a beta-sheet by introducing a residue with high beta-sheet forming propensity. All mutated residues are involved in forming complex, cooperative interaction networks that extend from the interior of the protein to its surface and which may therefore constitute "weak points" where BLA unfolding is initiated. This might explain the unexpectedly large effect induced by some of the substitutions on the kinetic stability of BLA. Our study shows that substantial protein stabilization can be achieved by stabilizing surface positions that participate in underlying cooperatively formed substructures. At such positions, even the apparently thermodynamically unfavorable introduction of hydrophobic residues should be explored. | |||
Kinetic stabilization of Bacillus licheniformis alpha-amylase through introduction of hydrophobic residues at the surface.,Machius M, Declerck N, Huber R, Wiegand G J Biol Chem. 2003 Mar 28;278(13):11546-53. Epub 2003 Jan 21. PMID:12540849<ref>PMID:12540849</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
</div> | |||
[[ | <div class="pdbe-citations 1ob0" style="background-color:#fffaf0;"></div> | ||
==See Also== | |||
*[[Amylase 3D structures|Amylase 3D structures]] | |||
== References == | |||
<references/> | |||
__TOC__ | |||
</StructureSection> | |||
[[Category: Bacillus licheniformis]] | [[Category: Bacillus licheniformis]] | ||
[[Category: | [[Category: Large Structures]] | ||
[[Category: Declerck | [[Category: Declerck N]] | ||
[[Category: Huber | [[Category: Huber R]] | ||
[[Category: Machius | [[Category: Machius M]] | ||
[[Category: Wiegand | [[Category: Wiegand G]] | ||