1b0v: Difference between revisions
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[[Image: | ==I40N MUTANT OF AZOTOBACTER VINELANDII FDI== | ||
<StructureSection load='1b0v' size='340' side='right' caption='[[1b0v]], [[Resolution|resolution]] 2.80Å' scene=''> | |||
== Structural highlights == | |||
<table><tr><td colspan='2'>[[1b0v]] is a 4 chain structure with sequence from [http://en.wikipedia.org/wiki/Azotobacter_vinelandii Azotobacter vinelandii]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1B0V OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1B0V FirstGlance]. <br> | |||
</td></tr><tr><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=F3S:FE3-S4+CLUSTER'>F3S</scene>, <scene name='pdbligand=SF4:IRON/SULFUR+CLUSTER'>SF4</scene><br> | |||
<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=1b0v FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1b0v OCA], [http://www.rcsb.org/pdb/explore.do?structureId=1b0v RCSB], [http://www.ebi.ac.uk/pdbsum/1b0v 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/b0/1b0v_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 [4Fe-4S](2+/+) cluster of Azotobacter vinelandii ferredoxin I (FdI) has an unusually low reduction potential (E(0')) relative to other structurally similar ferredoxins. Previous attempts to raise that E(0') by modification of surface charged residues were unsuccessful. In this study mutants were designed to alter the E(0') by substitution of polar residues for nonpolar residues near the cluster and by modification of backbone amides. Three FdI variants, P21G, I40N, and I40Q, were purified and characterized, and electrochemical E(0') measurements show that all had altered E(0') relative to native FdI. For P21G FdI and I40Q FdI, the E(0') increased by +42 and +53 mV, respectively validating the importance of dipole orientation in control of E(0'). Protein Dipole Langevin Dipole calculations based on models for those variants accurately predicted the direction of the change in E(0') while overestimating the magnitude. For I40N FdI, initial calculations based on the model predicted a +168 mV change in E(0') while a -33 mV change was observed. The x-ray structure of that variant, which was determined to 2.8 A, revealed a number of changes in backbone and side chain dipole orientation and in solvent accessibility, that were not predicted by the model and that were likely to influence E(0'). Subsequent Protein Dipole Langevin Dipole calculations (using the actual I40N x-ray structures) did quite accurately predict the observed change in E(0'). | |||
Alteration of the reduction potential of the [4Fe-4S](2+/+) cluster of Azotobacter vinelandii ferredoxin I.,Chen K, Tilley GJ, Sridhar V, Prasad GS, Stout CD, Armstrong FA, Burgess BK J Biol Chem. 1999 Dec 17;274(51):36479-87. PMID:10593945<ref>PMID:10593945</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
</div> | |||
==See Also== | ==See Also== | ||
*[[Ferredoxin|Ferredoxin]] | *[[Ferredoxin|Ferredoxin]] | ||
== References == | |||
== | <references/> | ||
< | __TOC__ | ||
</StructureSection> | |||
[[Category: Azotobacter vinelandii]] | [[Category: Azotobacter vinelandii]] | ||
[[Category: Burgess, B K.]] | [[Category: Burgess, B K.]] | ||
Revision as of 06:10, 7 August 2014
I40N MUTANT OF AZOTOBACTER VINELANDII FDII40N MUTANT OF AZOTOBACTER VINELANDII FDI
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 [4Fe-4S](2+/+) cluster of Azotobacter vinelandii ferredoxin I (FdI) has an unusually low reduction potential (E(0')) relative to other structurally similar ferredoxins. Previous attempts to raise that E(0') by modification of surface charged residues were unsuccessful. In this study mutants were designed to alter the E(0') by substitution of polar residues for nonpolar residues near the cluster and by modification of backbone amides. Three FdI variants, P21G, I40N, and I40Q, were purified and characterized, and electrochemical E(0') measurements show that all had altered E(0') relative to native FdI. For P21G FdI and I40Q FdI, the E(0') increased by +42 and +53 mV, respectively validating the importance of dipole orientation in control of E(0'). Protein Dipole Langevin Dipole calculations based on models for those variants accurately predicted the direction of the change in E(0') while overestimating the magnitude. For I40N FdI, initial calculations based on the model predicted a +168 mV change in E(0') while a -33 mV change was observed. The x-ray structure of that variant, which was determined to 2.8 A, revealed a number of changes in backbone and side chain dipole orientation and in solvent accessibility, that were not predicted by the model and that were likely to influence E(0'). Subsequent Protein Dipole Langevin Dipole calculations (using the actual I40N x-ray structures) did quite accurately predict the observed change in E(0'). Alteration of the reduction potential of the [4Fe-4S](2+/+) cluster of Azotobacter vinelandii ferredoxin I.,Chen K, Tilley GJ, Sridhar V, Prasad GS, Stout CD, Armstrong FA, Burgess BK J Biol Chem. 1999 Dec 17;274(51):36479-87. PMID:10593945[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences |
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