View source for 7nna


==Toxin Import Through the Antibiotic Efflux Channel TolC==
<StructureSection load='7nna' size='340' side='right'caption='[[7nna]], [[Resolution|resolution]] 1.90&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[7nna]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/"bacillus_pneumoniae"_(schroeter_1886)_flugge_1886 "bacillus pneumoniae" (schroeter 1886) flugge 1886]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=7NNA OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=7NNA FirstGlance]. <br>
</td></tr><tr id='NonStdRes'><td class="sblockLbl"><b>[[Non-Standard_Residue|NonStd Res:]]</b></td><td class="sblockDat"><scene name='pdbligand=MSE:SELENOMETHIONINE'>MSE</scene></td></tr>
<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">kca ([https://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=573 "Bacillus pneumoniae" (Schroeter 1886) Flugge 1886])</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=7nna FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=7nna OCA], [https://pdbe.org/7nna PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=7nna RCSB], [https://www.ebi.ac.uk/pdbsum/7nna PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=7nna ProSAT]</span></td></tr>
</table>
== Function ==
[[https://www.uniprot.org/uniprot/Q5V9K0_KLEPN Q5V9K0_KLEPN]] Colicins are polypeptide toxins produced by and active against E.coli and closely related bacteria.[ARBA:ARBA00003197] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Bacteria often secrete diffusible protein toxins (bacteriocins) to kill bystander cells during interbacterial competition. Here, we use biochemical, biophysical and structural analyses to show how a bacteriocin exploits TolC, a major outer-membrane antibiotic efflux channel in Gram-negative bacteria, to transport itself across the outer membrane of target cells. Klebicin C (KlebC), a rRNase toxin produced by Klebsiella pneumoniae, binds TolC of a related species (K. quasipneumoniae) with high affinity through an N-terminal, elongated helical hairpin domain common amongst bacteriocins. The KlebC helical hairpin opens like a switchblade to bind TolC. A cryo-EM structure of this partially translocated state, at 3.1 A resolution, reveals that KlebC associates along the length of the TolC channel. Thereafter, the unstructured N-terminus of KlebC protrudes beyond the TolC iris, presenting a TonB-box sequence to the periplasm. Association with proton-motive force-linked TonB in the inner membrane drives toxin import through the channel. Finally, we demonstrate that KlebC binding to TolC blocks drug efflux from bacteria. Our results indicate that TolC, in addition to its known role in antibiotic export, can function as a protein import channel for bacteriocins.

Toxin import through the antibiotic efflux channel TolC.,Housden NG, Webby MN, Lowe ED, El-Baba TJ, Kaminska R, Redfield C, Robinson CV, Kleanthous C Nat Commun. 2021 Jul 30;12(1):4625. doi: 10.1038/s41467-021-24930-y. PMID:34330923<ref>PMID:34330923</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 7nna" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Housden, N G]]
[[Category: Kleanthous, C]]
[[Category: Lowe, E D]]
[[Category: Antibiotic]]
[[Category: Import]]
[[Category: Toxin]]