1hxt: Difference between revisions
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[[Image: | ==OMPF PORIN MUTANT NQAAA== | ||
<StructureSection load='1hxt' size='340' side='right' caption='[[1hxt]], [[Resolution|resolution]] 2.40Å' scene=''> | |||
== Structural highlights == | |||
<table><tr><td colspan='2'>[[1hxt]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1HXT OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1HXT FirstGlance]. <br> | |||
</td></tr><tr><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=C8E:(HYDROXYETHYLOXY)TRI(ETHYLOXY)OCTANE'>C8E</scene><br> | |||
<tr><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[2omf|2omf]], [[1hxu|1hxu]], [[1hxx|1hxx]]</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=1hxt FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1hxt OCA], [http://www.rcsb.org/pdb/explore.do?structureId=1hxt RCSB], [http://www.ebi.ac.uk/pdbsum/1hxt 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/hx/1hxt_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 channel constriction of OmpF porin, a pore protein in the bacterial outer membrane, is highly charged due to the presence of three arginines (R42, R82, and R132) and two acidic residues (D113 and E117). The influence of these charges on ion conductance, ion selectivity, and voltage gating has been studied with mutants D113N/E117Q, R42A/R82A/R132A/D113N/E117Q, and V18K/G131K, which were designed to remove or add protein charge at the channel constriction. The crystal structures revealed no or only local changes compared to wild-type OmpF, thus allowing a comparative study. The single-channel conductance of the isosteric D113N/E117Q variant was found to be 2-fold reduced, and that of the pentuple mutant was 70% of the wild-type value, despite a considerably larger pore cross section. Ion selectivity was drastically altered by the mutations with cation/anion permeability ratios ranging from 1 to 12. Ion flow through these and eight other mutants, which have been characterized previously, was simulated by Brownian dynamics based on the detailed crystal structures. The calculated ion selectivity and relative channel conductance values agree well with the experimental data. This demonstrates that ion translocation through porin is mainly governed by pore geometry and charge, the two factors that are properly represented in the simulations. | |||
Role of charged residues at the OmpF porin channel constriction probed by mutagenesis and simulation.,Phale PS, Philippsen A, Widmer C, Phale VP, Rosenbusch JP, Schirmer T Biochemistry. 2001 May 29;40(21):6319-25. PMID:11371193<ref>PMID:11371193</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
</div> | |||
==See Also== | ==See Also== | ||
*[[Porin|Porin]] | *[[Porin|Porin]] | ||
== References == | |||
== | <references/> | ||
< | __TOC__ | ||
</StructureSection> | |||
[[Category: Escherichia coli]] | [[Category: Escherichia coli]] | ||
[[Category: Phale, P S.]] | [[Category: Phale, P S.]] | ||
Revision as of 15:06, 28 September 2014
OMPF PORIN MUTANT NQAAAOMPF PORIN MUTANT NQAAA
Structural highlights
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 PubMedThe channel constriction of OmpF porin, a pore protein in the bacterial outer membrane, is highly charged due to the presence of three arginines (R42, R82, and R132) and two acidic residues (D113 and E117). The influence of these charges on ion conductance, ion selectivity, and voltage gating has been studied with mutants D113N/E117Q, R42A/R82A/R132A/D113N/E117Q, and V18K/G131K, which were designed to remove or add protein charge at the channel constriction. The crystal structures revealed no or only local changes compared to wild-type OmpF, thus allowing a comparative study. The single-channel conductance of the isosteric D113N/E117Q variant was found to be 2-fold reduced, and that of the pentuple mutant was 70% of the wild-type value, despite a considerably larger pore cross section. Ion selectivity was drastically altered by the mutations with cation/anion permeability ratios ranging from 1 to 12. Ion flow through these and eight other mutants, which have been characterized previously, was simulated by Brownian dynamics based on the detailed crystal structures. The calculated ion selectivity and relative channel conductance values agree well with the experimental data. This demonstrates that ion translocation through porin is mainly governed by pore geometry and charge, the two factors that are properly represented in the simulations. Role of charged residues at the OmpF porin channel constriction probed by mutagenesis and simulation.,Phale PS, Philippsen A, Widmer C, Phale VP, Rosenbusch JP, Schirmer T Biochemistry. 2001 May 29;40(21):6319-25. PMID:11371193[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences |
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