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In vivo structure of the Legionella type II secretion system by electron cryotomography

Ghosal, Debnath and Kim, Ki Woo and Zheng, Huaixin and Kaplan, Mohammed and Truchan, Hilary K. and Lopez, Alberto E. and McIntire, Ian E. and Vogel, Joseph P. and Cianciotto, Nicholas P. and Jensen, Grant J. (2019) In vivo structure of the Legionella type II secretion system by electron cryotomography. Nature Microbiology, 4 (12). pp. 2101-2108. ISSN 2058-5276. PMCID PMC6879910.

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[img] Image (JPEG) (Extended Data Fig. 4: Position of the T2SS with respect to the PG layer in L. pneumophila) - Supplemental Material
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The type II secretion system (T2SS) is a multiprotein envelope-spanning assembly that translocates a wide range of virulence factors, enzymes and effectors through the outer membrane of many Gram-negative bacteria. Here, using electron cryotomography and subtomogram averaging methods, we reveal the in vivo structure of an intact T2SS imaged within the human pathogen Legionella pneumophila. Although the T2SS has only limited sequence and component homology with the evolutionarily related type IV pilus (T4P) system, we show that their overall architectures are remarkably similar. Despite similarities, there are also differences, including, for example, that the T2SS–ATPase complex is usually present but disengaged from the inner membrane, the T2SS has a much longer periplasmic vestibule and it has a short-lived flexible pseudopilus. Placing atomic models of the components into our electron cryotomography map produced a complete architectural model of the intact T2SS that provides insights into the structure and function of its components, its position within the cell envelope and the interactions between its different subcomplexes.

Item Type:Article
Related URLs:
URLURL TypeDescription ReadCube access Paper Correction ReadCube access - Publisher Correction CentralArticle
Ghosal, Debnath0000-0002-2227-0330
Kim, Ki Woo0000-0002-7010-0336
Zheng, Huaixin0000-0002-2529-7176
Kaplan, Mohammed0000-0002-0759-0459
Lopez, Alberto E.0000-0002-6218-5587
Vogel, Joseph P.0000-0002-8054-5021
Cianciotto, Nicholas P.0000-0002-9572-8322
Jensen, Grant J.0000-0003-1556-4864
Additional Information:© 2019 Springer Nature Limited. Received 19 January 2019; Accepted 07 October 2019; Published 21 November 2019. Data availability: The subtomogram averages of the L. pneumophila T2SS have been deposited in the Electron Microscopy Data Bank under the following accession codes: EMD-20713 (wild type, aligned on the OM part) and EMD-20712 (wild type, aligned on the IM part). All additional data/information are available from the authors upon request. The authors declare that all data supporting the findings of this study, including source data for Fig. 1, are available within the paper and its Supplementary Information. This work was supported by National Institutes of Health grants AI127401 to G.J.J. and AI043987 to N.P.C. ECT data were recorded at the Beckman Institute Resource Center for Transmission Electron Microcopy at Caltech and the cryo-EM facility at Janelia Research Campus. We thank D. Ortega, Y.-W. Chang and R.C. White for helpful discussions. M.K. is supported by a postdoctoral Rubicon fellowship from De Nederlandse Organisatie voor Wetenschappelijk Onderzoek. Author Contributions: D.G. and G.J.J. conceived the project. D.G. prepared samples and recorded and processed tomography data. D.G., K.W.K. and G.J.J. analysed data. H.Z., H.K.T., A.E.L., I.E.M., N.P.C. and J.P.V. generated and characterized L. pneumophila mutants. M.K. helped in model building. D.G., K.W.K., N.P.C. and G.J.J. wrote the manuscript with input from all the authors. The authors declare no competing interests.
Errata:In the version of this Letter originally published, the author Grant J. Jensen was mistakenly affiliated with Zhengzhou University. His affiliation has now been corrected to: Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA and Howard Hughes Medical Institute, Pasadena, CA, USA.
Funding AgencyGrant Number
Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO)UNSPECIFIED
Subject Keywords:Bacteriology; Cryoelectron tomography; Pathogens
Issue or Number:12
PubMed Central ID:PMC6879910
Record Number:CaltechAUTHORS:20190123-125316052
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Official Citation:Ghosal, D., Kim, K.W., Zheng, H. et al. In vivo structure of the Legionella type II secretion system by electron cryotomography. Nat Microbiol 4, 2101–2108 (2019) doi:10.1038/s41564-019-0603-6
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:92431
Deposited By: Tony Diaz
Deposited On:23 Jan 2019 22:20
Last Modified:19 Feb 2020 18:06

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