View source for 6qxm


==Cryo-EM structure of T7 bacteriophage portal protein, 12mer, open valve==
<SX load='6qxm' size='340' side='right' viewer='molstar' caption='[[6qxm]], [[Resolution|resolution]] 4.10&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[6qxm]] is a 12 chain structure with sequence from [http://en.wikipedia.org/wiki/Bpt7 Bpt7]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6QXM OCA]. For a <b>guided tour on the structure components</b> use [http://proteopedia.org/fgij/fg.htm?mol=6QXM FirstGlance]. <br>
</td></tr><tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[6qwp|6qwp]], [[6qx5|6qx5]], [[6r21|6r21]]</td></tr>
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://proteopedia.org/fgij/fg.htm?mol=6qxm FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6qxm OCA], [http://pdbe.org/6qxm PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=6qxm RCSB], [http://www.ebi.ac.uk/pdbsum/6qxm PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=6qxm ProSAT]</span></td></tr>
</table>
== Function ==
[[http://www.uniprot.org/uniprot/PORTL_BPT7 PORTL_BPT7]] Forms the portal vertex of the capsid. This portal plays critical roles in head assembly, genome packaging, neck/tail attachment, and genome ejection. The portal protein multimerizes as a single ring-shaped homododecamer arranged around a central channel.[HAMAP-Rule:MF_04120]<ref>PMID:15784250</ref> <ref>PMID:23884409</ref>  
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Double-stranded DNA bacteriophages package their genome at high pressure inside a procapsid through the portal, an oligomeric ring protein located at a unique capsid vertex. Once the DNA has been packaged, the tail components assemble on the portal to render the mature infective virion. The tail tightly seals the ejection conduit until infection, when its interaction with the host membrane triggers the opening of the channel and the viral genome is delivered to the host cell. Using high-resolution cryo-electron microscopy and X-ray crystallography, here we describe various structures of the T7 bacteriophage portal and fiber-less tail complex, which suggest a possible mechanism for DNA retention and ejection: a portal closed conformation temporarily retains the genome before the tail is assembled, whereas an open portal is found in the tail. Moreover, a fold including a seven-bladed beta-propeller domain is described for the nozzle tail protein.

Structures of T7 bacteriophage portal and tail suggest a viral DNA retention and ejection mechanism.,Cuervo A, Fabrega-Ferrer M, Machon C, Conesa JJ, Fernandez FJ, Perez-Luque R, Perez-Ruiz M, Pous J, Vega MC, Carrascosa JL, Coll M Nat Commun. 2019 Aug 20;10(1):3746. doi: 10.1038/s41467-019-11705-9. PMID:31431626<ref>PMID:31431626</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 6qxm" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</SX>
[[Category: Bpt7]]
[[Category: Large Structures]]
[[Category: Carrascosa, J L]]
[[Category: Coll, M]]
[[Category: Cuervo, A]]
[[Category: Fabrega-Ferrer, M]]
[[Category: Fernandez, F J]]
[[Category: Machon, C]]
[[Category: Perez-Luque, R]]
[[Category: Pous, J]]
[[Category: Vega, M C]]
[[Category: Dna packaging]]
[[Category: Viral protein]]