The C-terminal tail of the bacterial translocation ATPase SecA modulates its activity

  1. Mohammed Jamshad
  2. Timothy J Knowles
  3. Scott A White
  4. Douglas G Ward
  5. Fiyaz Mohammed
  6. Kazi Fahmida Rahman
  7. Max Wynne
  8. Gareth W Hughes
  9. Günter Kramer
  10. Bernd Bukau
  11. Damon Huber  Is a corresponding author
  1. University of Birmingham, United Kingdom
  2. Heidelberg University, Germany
  3. University of Heidelberg, Germany

Abstract

In bacteria, the translocation of proteins across the cytoplasmic membrane by the Sec machinery requires the ATPase SecA. SecA can bind ribosomes and recognise nascent substrate proteins, but the molecular mechanism of recognition is unknown. We investigated the role of the C-terminal tail (CTT) of SecA in nascent polypeptide recognition. The CTT consists of a flexible linker (FLD) and a small metal-binding domain (MBD). Phylogenetic analysis and ribosome binding experiments indicated that the MBD interacts with 70S ribosomes. Disruption of the MBD only or the entire CTT had opposing effects on ribosome binding, substrate-protein binding, ATPase activity and in vivo function, suggesting that the CTT influences the conformation of SecA. Site-specific crosslinking indicated that F399 in SecA contacts ribosomal protein uL29, and binding to nascent chains disrupts this interaction. Structural studies provided insight into the CTT-mediated conformational changes in SecA. Our results suggest a mechanism for nascent substrate protein recognition.

Data availability

X-ray crystallography data are deposited in PDB under accession code 6GOX.Small-angle x-ray scattering data are deposited in SASBDB under accession codes SASDDY9, SASDDZ9 and SASDE22.

The following data sets were generated
    1. Knowles T
    2. Jamshad M
    3. Huber D
    (2018) SecA
    Small Angle Scattering Biological Data Bank, SASDDY9.
    1. Knowles T
    2. Jamshad M
    3. Huber D
    (2018) SecAΔMBD
    Small Angle Scattering Biological Data Bank, SASDDZ9.
    1. Knowles T
    2. Jamshad M
    3. Huber D
    (2018) SecAΔCTT
    Small Angle Scattering Biological Data Bank, SASDE22.

Article and author information

Author details

  1. Mohammed Jamshad

    School of Biosciences, University of Birmingham, Birmingham, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  2. Timothy J Knowles

    School of Biosciences, University of Birmingham, Birmingham, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  3. Scott A White

    School of Biosciences, University of Birmingham, Birmingham, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  4. Douglas G Ward

    Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  5. Fiyaz Mohammed

    Institute of Immunology and Immunotherapy, University of Birmingham, Birmingham, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  6. Kazi Fahmida Rahman

    School of Biosciences, University of Birmingham, Birmingham, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  7. Max Wynne

    School of Biosciences, University of Birmingham, Birmingham, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  8. Gareth W Hughes

    School of Biosciences, University of Birmingham, Birmingham, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-1228-6152
  9. Günter Kramer

    Center for Molecular Biology, Heidelberg University, Heidelberg, Germany
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-7552-8393
  10. Bernd Bukau

    Center for Molecular Biology, University of Heidelberg, Heidelberg, Germany
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0521-7199
  11. Damon Huber

    School of Biosciences, University of Birmingham, Birmingham, United Kingdom
    For correspondence
    d.huber@bham.ac.uk
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-7367-3244

Funding

Biotechnology and Biological Sciences Research Council (BB/L019434/1)

  • Mohammed Jamshad
  • Damon Huber

Biotechnology and Biological Sciences Research Council (BB/P009840/1)

  • Timothy J Knowles
  • Gareth W Hughes

Biotechnology and Biological Sciences Research Council (MIBTP)

  • Max Wynne

Deutsche Forschungsgemeinschaft (FOR 1805)

  • Günter Kramer
  • Bernd Bukau

Deutsche Forschungsgemeinschaft (SFB 638)

  • Günter Kramer
  • Bernd Bukau

Wellcome (099266/Z/12/Z)

  • Fiyaz Mohammed

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Ramanujan S Hegde, MRC Laboratory of Molecular Biology, United Kingdom

Version history

  1. Received: May 10, 2019
  2. Accepted: June 26, 2019
  3. Accepted Manuscript published: June 27, 2019 (version 1)
  4. Version of Record published: July 10, 2019 (version 2)

Copyright

© 2019, Jamshad et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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  1. Mohammed Jamshad
  2. Timothy J Knowles
  3. Scott A White
  4. Douglas G Ward
  5. Fiyaz Mohammed
  6. Kazi Fahmida Rahman
  7. Max Wynne
  8. Gareth W Hughes
  9. Günter Kramer
  10. Bernd Bukau
  11. Damon Huber
(2019)
The C-terminal tail of the bacterial translocation ATPase SecA modulates its activity
eLife 8:e48385.
https://doi.org/10.7554/eLife.48385

Share this article

https://doi.org/10.7554/eLife.48385

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