7oo8: Difference between revisions
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==Mechanosensitive channel MscS solubilized with LMNG in closed conformation with added lipid== | |||
<StructureSection load='7oo8' size='340' side='right'caption='[[7oo8]], [[Resolution|resolution]] 3.70Å' scene=''> | |||
== Structural highlights == | |||
<table><tr><td colspan='2'>[[7oo8]] is a 7 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=7OO8 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=7OO8 FirstGlance]. <br> | |||
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Electron Microscopy, [[Resolution|Resolution]] 3.7Å</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=7oo8 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=7oo8 OCA], [https://pdbe.org/7oo8 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=7oo8 RCSB], [https://www.ebi.ac.uk/pdbsum/7oo8 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=7oo8 ProSAT]</span></td></tr> | |||
</table> | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
The mechanosensitive channel of small conductance (MscS) protects bacteria against hypoosmotic shock. It can sense the tension in the surrounding membrane and releases solutes if the pressure in the cell is getting too high. The membrane contacts MscS at sensor paddles, but lipids also leave the membrane and move along grooves between the paddles to reside as far as 15 A away from the membrane in hydrophobic pockets. One sensing model suggests that a higher tension pulls lipids from the grooves back to the membrane, which triggers gating. However, it is still unclear to what degree this model accounts for sensing and what contribution the direct interaction of the membrane with the channel has. Here, we show that MscS opens when it is sufficiently delipidated by incubation with the detergent dodecyl-beta-maltoside or the branched detergent lauryl maltose neopentyl glycol. After addition of detergent-solubilized lipids, it closes again. These results support the model that lipid extrusion causes gating: Lipids are slowly removed from the grooves and pockets by the incubation with detergent, which triggers opening. Addition of lipids in micelles allows lipids to migrate back into the pockets, which closes the channel even in the absence of a membrane. Based on the distribution of the aliphatic chains in the open and closed conformation, we propose that during gating, lipids leave the complex on the cytosolic leaflet at the height of highest lateral tension, while on the periplasmic side, lipids flow into gaps, which open between transmembrane helices. | |||
Mechanosensitive channel gating by delipidation.,Flegler VJ, Rasmussen A, Borbil K, Boten L, Chen HA, Deinlein H, Halang J, Hellmanzik K, Loffler J, Schmidt V, Makbul C, Kraft C, Hedrich R, Rasmussen T, Bottcher B Proc Natl Acad Sci U S A. 2021 Aug 17;118(33):e2107095118. doi: , 10.1073/pnas.2107095118. PMID:34376558<ref>PMID:34376558</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
[[Category: | </div> | ||
<div class="pdbe-citations 7oo8" style="background-color:#fffaf0;"></div> | |||
==See Also== | |||
*[[Ion channels 3D structures|Ion channels 3D structures]] | |||
== References == | |||
<references/> | |||
__TOC__ | |||
</StructureSection> | |||
[[Category: Escherichia coli]] | |||
[[Category: Large Structures]] | |||
[[Category: Boettcher B]] | |||
[[Category: Flegler VJ]] | |||
[[Category: Rasmussen T]] | |||