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5mg3
From Proteopedia
(Difference between revisions)
(New page: '''Unreleased structure''' The entry 5mg3 is ON HOLD until sometime in the future Authors: Christiane Schaffitzel, Mathieu Botte Description: EM fitted model of bacterial holo-transloc...) |
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| - | '''Unreleased structure''' | ||
| - | + | ==EM fitted model of bacterial holo-translocon== | |
| + | <SX load='5mg3' size='340' side='right' viewer='molstar' caption='[[5mg3]], [[Resolution|resolution]] 14.00Å' scene=''> | ||
| + | == Structural highlights == | ||
| + | <table><tr><td colspan='2'>[[5mg3]] is a 6 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=5MG3 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=5MG3 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]] 14Å</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=5mg3 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5mg3 OCA], [https://pdbe.org/5mg3 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=5mg3 RCSB], [https://www.ebi.ac.uk/pdbsum/5mg3 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=5mg3 ProSAT]</span></td></tr> | ||
| + | </table> | ||
| + | == Function == | ||
| + | [https://www.uniprot.org/uniprot/SECY_ECOLI SECY_ECOLI] The central subunit of the protein translocation channel SecYEG. Consists of two halves formed by TMs 1-5 and 6-10. These two domains form a lateral gate at the front which open onto the bilayer between TMs 2 and 7, and are clamped together by SecE at the back. The channel is closed by both a pore ring composed of hydrophobic SecY resides and a short helix (helix 2A) on the extracellular side of the membrane which forms a plug. The plug probably moves laterally to allow the channel to open. The ring and the pore may move independently. SecY is required to insert newly synthesized SecY into the inner membrane. Overexpression of some hybrid proteins has been thought to jam the protein secretion apparatus resulting in cell death; while this may be true, overexpression also results in FtsH-mediated degradation of SecY.[HAMAP-Rule:MF_01465] | ||
| + | <div style="background-color:#fffaf0;"> | ||
| + | == Publication Abstract from PubMed == | ||
| + | The conserved SecYEG protein-conducting channel and the accessory proteins SecDF-YajC and YidC constitute the bacterial holo-translocon (HTL), capable of protein-secretion and membrane-protein insertion. By employing an integrative approach combining small-angle neutron scattering (SANS), low-resolution electron microscopy and biophysical analyses we determined the arrangement of the proteins and lipids within the super-complex. The results guided the placement of X-ray structures of individual HTL components and allowed the proposal of a model of the functional translocon. Their arrangement around a central lipid-containing pool conveys an unexpected, but compelling mechanism for membrane-protein insertion. The periplasmic domains of YidC and SecD are poised at the protein-channel exit-site of SecY, presumably to aid the emergence of translocating polypeptides. The SecY lateral gate for membrane-insertion is adjacent to the membrane 'insertase' YidC. Absolute-scale SANS employing a novel contrast-match-point analysis revealed a dynamic complex adopting open and compact configurations around an adaptable central lipid-filled chamber, wherein polytopic membrane-proteins could fold, sheltered from aggregation and proteolysis. | ||
| - | + | A central cavity within the holo-translocon suggests a mechanism for membrane protein insertion.,Botte M, Zaccai NR, Nijeholt JL, Martin R, Knoops K, Papai G, Zou J, Deniaud A, Karuppasamy M, Jiang Q, Roy AS, Schulten K, Schultz P, Rappsilber J, Zaccai G, Berger I, Collinson I, Schaffitzel C Sci Rep. 2016 Dec 7;6:38399. doi: 10.1038/srep38399. PMID:27924919<ref>PMID:27924919</ref> | |
| - | + | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |
| - | [[Category: | + | </div> |
| - | [[Category: | + | <div class="pdbe-citations 5mg3" style="background-color:#fffaf0;"></div> |
| + | |||
| + | ==See Also== | ||
| + | *[[Insertase|Insertase]] | ||
| + | *[[Preprotein translocase 3D structures|Preprotein translocase 3D structures]] | ||
| + | == References == | ||
| + | <references/> | ||
| + | __TOC__ | ||
| + | </SX> | ||
| + | [[Category: Escherichia coli]] | ||
| + | [[Category: Large Structures]] | ||
| + | [[Category: Botte M]] | ||
| + | [[Category: Schaffitzel C]] | ||
Current revision
EM fitted model of bacterial holo-translocon
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