2mme: Difference between revisions

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 ==Hybrid structure of the Shigella flexneri MxiH Type three secretion system needle==
-<StructureSection load='2mme' size='340' side='right' caption='[[2mme]], [[Resolution|resolution]] 7.70&Aring;, [[NMR_Ensembles_of_Models | 10 NMR models]]' scene=''>
+<SX load='2mme' size='340' side='right' viewer='molstar' caption='[[2mme]], [[Resolution|resolution]] 7.70&Aring;' scene=''>
 == Structural highlights ==
-<table><tr><td colspan='2'>[[2mme]] is a 29 chain structure. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2MME OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2MME FirstGlance]. <br>
+<table><tr><td colspan='2'>[[2mme]] is a 29 chain structure with sequence from [https://en.wikipedia.org/wiki/Shigella_flexneri Shigella flexneri]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2MME OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2MME FirstGlance]. <br>
-</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=2mme FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2mme OCA], [http://www.rcsb.org/pdb/explore.do?structureId=2mme RCSB], [http://www.ebi.ac.uk/pdbsum/2mme PDBsum]</span></td></tr>
+</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Electron Microscopy , Hybrid , Solid-state NMR, [[Resolution|Resolution]] 7.7&#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=2mme FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2mme OCA], [https://pdbe.org/2mme PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2mme RCSB], [https://www.ebi.ac.uk/pdbsum/2mme PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2mme ProSAT]</span></td></tr>
 </table>
+== Function ==
+[https://www.uniprot.org/uniprot/Q6XVY0_SHIFL Q6XVY0_SHIFL]
 <div style="background-color:#fffaf0;">
 == Publication Abstract from PubMed ==
-Type III secretion systems of Gram-negative bacteria form injection devices that deliver effector proteins into eukaryotic cells during infection. They span both bacterial membranes and the extracellular space to connect with the host cell plasma membrane. Their extracellular portion is a needle-like, hollow tube that serves as a secretion conduit for effector proteins. The needle of Shigella flexneri is approximately 50-nm long and 7-nm thick and is made by the helical assembly of one protein, MxiH. We provide a 7-A resolution 3D image reconstruction of the Shigella needle by electron cryomicroscopy, which resolves alpha-helices and a beta-hairpin that has never been observed in the crystal and solution structures of needle proteins, including MxiH. An atomic model of the needle based on the 3D-density map, in comparison with that of the bacterial-flagellar filament, provides insights into how such a thin tubular structure is stably assembled by intricate intermolecular interactions. The map also illuminates how the needle-length control protein functions as a ruler within the central channel during export of MxiH for assembly at the distal end of the needle, and how the secretion-activation signal may be transduced through a conformational change of the needle upon host-cell contact.
+We introduce a general hybrid approach for determining the structures of supramolecular assemblies. Cryo-electron microscopy (cryo-EM) data define the overall envelope of the assembly and rigid-body orientation of the subunits while solid-state nuclear magnetic resonance (ssNMR) chemical shifts and distance constraints define the local secondary structure, protein fold and inter-subunit interactions. Finally, Rosetta structure calculations provide a general framework to integrate the different sources of structural information. Combining a 7.7-A cryo-EM density map and 996 ssNMR distance constraints, the structure of the type-III secretion system needle of Shigella flexneri is determined to a precision of 0.4 A. The calculated structures are cross-validated using an independent data set of 691 ssNMR constraints and scanning transmission electron microscopy measurements. The hybrid model resolves the conformation of the non-conserved N terminus, which occupies a protrusion in the cryo-EM density, and reveals conserved pore residues forming a continuous pattern of electrostatic interactions, thereby suggesting a mechanism for effector protein translocation.
-Structure of a type III secretion needle at 7-A resolution provides insights into its assembly and signaling mechanisms.,Fujii T, Cheung M, Blanco A, Kato T, Blocker AJ, Namba K Proc Natl Acad Sci U S A. 2012 Mar 2. PMID:22388746<ref>PMID:22388746</ref>
+High-resolution structure of the Shigella type-III secretion needle by solid-state NMR and cryo-electron microscopy.,Demers JP, Habenstein B, Loquet A, Kumar Vasa S, Giller K, Becker S, Baker D, Lange A, Sgourakis NG Nat Commun. 2014 Sep 29;5:4976. doi: 10.1038/ncomms5976. PMID:25264107<ref>PMID:25264107</ref>
 From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
 </div>
+<div class="pdbe-citations 2mme" style="background-color:#fffaf0;"></div>
 == References ==
 <references/>
 __TOC__
-</StructureSection>
+</SX>
-[[Category: Baker, D]]
+[[Category: Large Structures]]
-[[Category: Becker, S]]
-[[Category: Demers, J P]]
-[[Category: Habenstein, B]]
-[[Category: Lange, A]]
-[[Category: Loquet, A]]
-[[Category: Sgourakis, N G]]
-[[Category: Vasa, S K]]
-[[Category: Filamentous protein]]
-[[Category: Helical assembly]]
-[[Category: Hybrid method]]
-[[Category: Protein translocation]]
-[[Category: Protein transport]]
-[[Category: Rosetta]]
 [[Category: Shigella flexneri]]
-[[Category: Type-three secretion system]]
+[[Category: Baker D]]
+[[Category: Becker S]]
+[[Category: Demers JP]]
+[[Category: Habenstein B]]
+[[Category: Lange A]]
+[[Category: Loquet A]]
+[[Category: Sgourakis NG]]
+[[Category: Vasa SK]]