1grm: Difference between revisions
New page: left|200px<br /><applet load="1grm" size="450" color="white" frame="true" align="right" spinBox="true" caption="1grm" /> '''REFINEMENT OF THE SPATIAL STRUCTURE OF THE G... |
No edit summary |
||
(18 intermediate revisions by the same user not shown) | |||
Line 1: | Line 1: | ||
== | ==REFINEMENT OF THE SPATIAL STRUCTURE OF THE GRAMICIDIN A TRANSMEMBRANE ION-CHANNEL (RUSSIAN)== | ||
The spatial structure of the gramicidin A (GA) transmembrane ion-channel | <StructureSection load='1grm' size='340' side='right'caption='[[1grm]]' scene=''> | ||
== Structural highlights == | |||
<table><tr><td colspan='2'>[[1grm]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Brevibacillus_brevis Brevibacillus brevis]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1GRM OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1GRM FirstGlance]. <br> | |||
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Solution NMR, 5 models</td></tr> | |||
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=DLE:D-LEUCINE'>DLE</scene>, <scene name='pdbligand=DVA:D-VALINE'>DVA</scene>, <scene name='pdbligand=ETA:ETHANOLAMINE'>ETA</scene>, <scene name='pdbligand=FVA:N-FORMYL-L-VALINE'>FVA</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=1grm FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1grm OCA], [https://pdbe.org/1grm PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1grm RCSB], [https://www.ebi.ac.uk/pdbsum/1grm PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1grm ProSAT]</span></td></tr> | |||
</table> | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
The spatial structure of the gramicidin A (GA) transmembrane ion-channel was refined on the base of cross-peak volumes measured in NOESY spectra (mixing time tau m = 100 and 200 ms). The refinement methods included the comparison of experimental cross-peak volumes with those calculated for low-energy GA conformations, dynamic averaging of the low-energy conformation set and restrained energy minimization. Accuracy of the spatial structure determination was estimated by the penalty function Fr defined as a root mean square deviation of interproton distances corresponding to the calculated and experimental cross-peak volumes. As the initial conformation we used the right-handed pi 6,3 LD pi 6,3 LD helix established on the base of NMR data regardless of the cross-peak volumes. The conformation is in a good agreement with NOE cross-peak volumes (Fr 0.2 to 0.5 A depending on NOESY spectrum). For a number of NOEs formed by the side chain protons, distances errors were found as much as 0.5-2.0 A. Restrained energy minimization procedure had little further success. However some of these errors were eliminated by the change in torsional angle chi 2 of D-Leu12 and dynamic averaging of the Val7 side chain conformations. Apparently, majority of deviations of the calculated and experimental cross-peak volumes are due to the intramolecular mobility of GA and cannot be eliminated within the framework of rigid globule model. In summary the spatial structure of GA ion-channel can be thought as a set of low-energy conformations, differing by the side chain torsion angles chi 1 Val7 and chi 2 D-Leu4 and D-Leu10 and the orientation of the C-terminal ethanolamine group. Root mean square differences between the atomic coordinates of conformations are in the range of 0.3-0.8 A. | |||
[Refinement of the spatial structure of the gramicidin A ion channel],Lomize AL, Orekhov VIu, Arsen'ev AS Bioorg Khim. 1992 Feb;18(2):182-200. PMID:1376600<ref>PMID:1376600</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
</div> | |||
<div class="pdbe-citations 1grm" style="background-color:#fffaf0;"></div> | |||
==See Also== | |||
*[[Gramicidin|Gramicidin]] | |||
== References == | |||
<references/> | |||
__TOC__ | |||
</StructureSection> | |||
[[Category: Brevibacillus brevis]] | |||
[[Category: Large Structures]] | |||
[[Category: Arseniev AS]] | |||
[[Category: Barsukov IL]] | |||
[[Category: Bystrov VF]] | |||
[[Category: Lomize AL]] | |||
[[Category: Orekhov VY]] |
Latest revision as of 03:01, 21 November 2024
REFINEMENT OF THE SPATIAL STRUCTURE OF THE GRAMICIDIN A TRANSMEMBRANE ION-CHANNEL (RUSSIAN)REFINEMENT OF THE SPATIAL STRUCTURE OF THE GRAMICIDIN A TRANSMEMBRANE ION-CHANNEL (RUSSIAN)
Structural highlights
Publication Abstract from PubMedThe spatial structure of the gramicidin A (GA) transmembrane ion-channel was refined on the base of cross-peak volumes measured in NOESY spectra (mixing time tau m = 100 and 200 ms). The refinement methods included the comparison of experimental cross-peak volumes with those calculated for low-energy GA conformations, dynamic averaging of the low-energy conformation set and restrained energy minimization. Accuracy of the spatial structure determination was estimated by the penalty function Fr defined as a root mean square deviation of interproton distances corresponding to the calculated and experimental cross-peak volumes. As the initial conformation we used the right-handed pi 6,3 LD pi 6,3 LD helix established on the base of NMR data regardless of the cross-peak volumes. The conformation is in a good agreement with NOE cross-peak volumes (Fr 0.2 to 0.5 A depending on NOESY spectrum). For a number of NOEs formed by the side chain protons, distances errors were found as much as 0.5-2.0 A. Restrained energy minimization procedure had little further success. However some of these errors were eliminated by the change in torsional angle chi 2 of D-Leu12 and dynamic averaging of the Val7 side chain conformations. Apparently, majority of deviations of the calculated and experimental cross-peak volumes are due to the intramolecular mobility of GA and cannot be eliminated within the framework of rigid globule model. In summary the spatial structure of GA ion-channel can be thought as a set of low-energy conformations, differing by the side chain torsion angles chi 1 Val7 and chi 2 D-Leu4 and D-Leu10 and the orientation of the C-terminal ethanolamine group. Root mean square differences between the atomic coordinates of conformations are in the range of 0.3-0.8 A. [Refinement of the spatial structure of the gramicidin A ion channel],Lomize AL, Orekhov VIu, Arsen'ev AS Bioorg Khim. 1992 Feb;18(2):182-200. PMID:1376600[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences |
|