6ctd: Difference between revisions

<table><tr><td colspan='2'>[[6ctd]] is a 10 chain structure with sequence from [http://en.wikipedia.org/wiki/Mycta Mycta]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6CTD OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=6CTD FirstGlance]. <br>

</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=AU:GOLD+ION'>AU</scene></td></tr>

<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">mscL, MRA_0992 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=419947 MYCTA])</td></tr>

<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=6ctd FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6ctd OCA], [http://pdbe.org/6ctd PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=6ctd RCSB], [http://www.ebi.ac.uk/pdbsum/6ctd PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=6ctd ProSAT]</span></td></tr>

[[http://www.uniprot.org/uniprot/MSCL_MYCTA MSCL_MYCTA]] Channel that opens in response to stretch forces in the membrane lipid bilayer. The force required to trigger channel opening depends on the nature of the membrane lipids; the presence of phosphatidylinositol enhances mechanosensitivity of the channel. May participate in the regulation of osmotic pressure changes within the cell.[UniProtKB:P9WJN5]

Microbial survival in dynamic environments requires the ability to successfully respond to abrupt changes in osmolarity. The mechanosensitive channel of large conductance (MscL) is a ubiquitous channel that facilitates the survival of bacteria and archaea under severe osmotic downshock conditions by relieving excess turgor pressure in response to increased membrane tension. A prominent structural feature of MscL, the cytoplasmic C-terminal domain, has been suggested to influence channel assembly and function. In this report, we describe the X-ray crystal structure and electrophysiological properties of a C-terminal domain truncation of the Mycobacterium tuberculosis MscL (MtMscLDeltaC). A crystal structure of MtMscLDeltaC solubilized in the detergent n-dodecyl-beta-D-maltopyranoside reveals the pentameric, closed state-like architecture for the membrane spanning region observed in the previously solved full-length MtMscL. Electrophysiological characterization demonstrates that MtMscLDeltaC retains mechanosensitivity, but with conductance and tension sensitivity more closely resembling full length EcMscL than MtMscL. This study establishes that the C-terminal domain of MtMscL is not required for oligomerization of the full-length channel, but rather influences the tension sensitivity and conductance properties of the channel. The collective picture that emerges from these data is that each MscL channel structure has characteristic features, highlighting the importance of studying multiple homologs.

 

== References ==

[[Category: Mycta]]

[[Category: Herrera, N]]

[[Category: Rees, D C]]

[[Category: Membrane protein]]