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-Structure paper
Title | Cryo-EM structure of the extended type VI secretion system sheath-tube complex. |
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Journal, issue, pages | Nat Microbiol, Vol. 2, Issue 11, Page 1507-1512, Year 2017 |
Publish date | Sep 25, 2017 |
Authors | Jing Wang / Maximilian Brackmann / Daniel Castaño-Díez / Mikhail Kudryashev / Kenneth N Goldie / Timm Maier / Henning Stahlberg / Marek Basler / |
PubMed Abstract | The bacterial type VI secretion system (T6SS) uses contraction of a long sheath to quickly thrust a tube with associated effectors across membranes of eukaryotic and bacterial cells . Only limited ...The bacterial type VI secretion system (T6SS) uses contraction of a long sheath to quickly thrust a tube with associated effectors across membranes of eukaryotic and bacterial cells . Only limited structural information is available about the inherently unstable precontraction state of the T6SS. Here, we obtain a 3.7 Å resolution structure of a non-contractile sheath-tube complex using cryo-electron microscopy and show that it resembles the extended T6SS inside Vibrio cholerae cells. We build a pseudo-atomic model of the complete sheath-tube assembly, which provides a mechanistic understanding of coupling sheath contraction with pushing and rotating the inner tube for efficient target membrane penetration. Our data further show that sheath contraction exposes a buried recognition domain to specifically trigger the disassembly and recycling of the T6SS sheath by the cognate ATP-dependent unfoldase ClpV. |
External links | Nat Microbiol / PubMed:28947741 |
Methods | EM (subtomogram averaging) / EM (helical sym.) |
Resolution | 3.7 - 17.4 Å |
Structure data | EMDB-3563: EMDB-3564: EMDB-3566: VipA-N3, non-contractile sheath of the type VI secretion system |
Source |
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Keywords | TRANSPORT PROTEIN / Type IV secretion system / protein export / PROTEIN TRANSPORT / Bacterial type VI secretion system / STRUCTURAL PROTEIN / T6SS / extended conformation / vibrio cholerae |