View source for 2oau


==Mechanosensitive Channel of Small Conductance (MscS)==
<StructureSection load='2oau' size='340' side='right'caption='[[2oau]], [[Resolution|resolution]] 3.70&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[2oau]] is a 7 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. This structure supersedes the now removed PDB entry [http://oca.weizmann.ac.il/oca-bin/send-pdb?obs=1&id=1mxm 1mxm]. The November 2008 RCSB PDB [https://pdb.rcsb.org/pdb/static.do?p=education_discussion/molecule_of_the_month/index.html Molecule of the Month] feature on ''Mechanosensitive Channels''  by David Goodsell is [https://dx.doi.org/10.2210/rcsb_pdb/mom_2008_11 10.2210/rcsb_pdb/mom_2008_11]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2OAU OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2OAU 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]] 3.7&#8491;</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=2oau FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2oau OCA], [https://pdbe.org/2oau PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2oau RCSB], [https://www.ebi.ac.uk/pdbsum/2oau PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2oau ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/MSCS_ECOLI MSCS_ECOLI] Mechanosensitive channel that participates in the regulation of osmotic pressure changes within the cell, opening in response to stretch forces in the membrane lipid bilayer, without the need for other proteins. Forms an ion channel of 1.0 nanosiemens conductance with a slight preference for anions. The channel is sensitive to voltage; as the membrane is depolarized, less tension is required to open the channel and vice versa. The channel is characterized by short bursts of activity that last for a few seconds.  The channel pore is formed by TM3 and the loop between TM2 and TM3. After a sharp turn at Gly-113, an alpha-helix (residues 114-127) is oriented nearly parallel to the plane of the putative lipid bilayer. On the intracellular side of the channel, the permeation pathway of MscS does not connect directly to the cytoplasm but instead opens to a large chamber that is connected to the cytoplasm. This chamber resembles a molecular filter that could serve to prescreen large molecules before they are allowed passage to the transmembrane pore. The TM1 and TM2 helices appear to be likely candidates for mediating the tension and voltage sensitivities of MscS. Gating requires large rearrangements of at least the C-terminus.
== 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/oa/2oau_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=2oau ConSurf].
<div style="clear:both"></div>

==See Also==
*[[Ion channels 3D structures|Ion channels 3D structures]]
__TOC__
</StructureSection>
[[Category: Escherichia coli]]
[[Category: Large Structures]]
[[Category: Mechanosensitive Channels]]
[[Category: RCSB PDB Molecule of the Month]]
[[Category: Barclay MT]]
[[Category: Bass RB]]
[[Category: Rees DC]]
[[Category: Steinbacher S]]
[[Category: Strop P]]