Structure of the cholera toxin secretion channel in its closed state

Research output: Contribution to journalArticlepeer-review

121 Scopus citations

Abstract

The type II secretion system (T2SS) is a macromolecular complex spanning the inner and outer membranes of Gram-negative bacteria. Remarkably, the T2SS secretes folded proteins, including multimeric assemblies such as cholera toxin and heat-labile enterotoxin from Vibrio cholerae and enterotoxigenic Escherichia coli, respectively. The major outer membrane T2SS protein is the 'secretin' GspD. Cryo-EM reconstruction of the V. cholerae secretin at 19-Å resolution reveals a dodecameric structure reminiscent of a barrel, with a large channel at its center that contains a closed periplasmic gate. The GspD periplasmic domain forms a vestibule with a conserved constriction, and it binds to a pentameric exoprotein and to the trimeric tip of the T2SS pseudopilus. By combining our results with structures of the cholera toxin and T2SS pseudopilus tip, we provide a structural basis for a possible secretion mechanism of the T2SS.

Original languageEnglish
Pages (from-to)1226-1232
Number of pages7
JournalNature Structural and Molecular Biology
Volume17
Issue number10
DOIs
StatePublished - Oct 2010

Funding

We thank the Murdock Charitable Trust and the Washington Research Foundation for generous support of our cryo-EM facility. We are grateful to J. Sun, M. Gonen, B. Vollmar and S. Turley for contributions to the earlier stages of this work; M. Bagdasarian (Michigan State University) for a VcGspD-containing plasmid; and J. DelaRosa for assistance with protein preparation. We thank A. J. Merz for helpful discussions. We thank N. Korotkova and P. Wallace for discussion of SPR experiments. Part of this work was conducted at the University of Washington NanoTech User Facility, a member of the US National Science Foundation (NSF) National Nanotechnology Infrastructure Network (NNIN). This research is supported by the US National Institutes of Health grant AI34501. The Gonen laboratory is supported in part by the Howard Hughes Medical Institute Early Career Scientist program.

FundersFunder number
U.S. Department of Energy Chinese Academy of Sciences Guangzhou Municipal Science and Technology Project Oak Ridge National Laboratory Extreme Science and Engineering Discovery Environment National Science Foundation National Energy Research Scientific Computing Center National Natural Science Foundation of China
National Institutes of Health (NIH)
Howard Hughes Medical Institute
Division of Microbiology and Infectious Diseases, National Institute of Allergy and Infectious DiseasesR01AI034501
M.J. Murdock Charitable Trust
Washington Research Foundation

    UN SDGs

    This output contributes to the following UN Sustainable Development Goals (SDGs)

    1. SDG 3 - Good Health and Well-being
      SDG 3 Good Health and Well-being

    ASJC Scopus subject areas

    • Structural Biology
    • Molecular Biology

    Fingerprint

    Dive into the research topics of 'Structure of the cholera toxin secretion channel in its closed state'. Together they form a unique fingerprint.

    Cite this