Septal secretion of protein A in Staphylococcus aureus requires SecA and lipoteichoic acid synthesis

  1. Wenqi Yu
  2. Dominique M Missiakas
  3. Olaf Schneewind  Is a corresponding author
  1. University of Chicago, United States

Abstract

Surface proteins of Staphylococcus aureus are secreted across septal membranes for assembly into the bacterial cross-wall. This localized secretion requires the YSIRK/GXXS motif signal peptide, however the mechanisms supporting precursor trafficking are not known. We show here that the signal peptide of staphylococcal protein A (SpA) is cleaved at the YSIRK/GXXS motif. A SpA signal peptide mutant defective for YSIRK/GXXS cleavage is also impaired for septal secretion and co-purifies with SecA, SecDF and LtaS. SecA depletion blocks precursor targeting to septal membranes, whereas deletion of secDF diminishes SpA secretion into the cross-wall. Depletion of LtaS blocks lipoteichoic acid synthesis and abolishes SpA precursor trafficking to septal membranes. We propose a model whereby SecA directs SpA precursors to lipoteichoic acid-rich septal membranes for YSIRK/GXXS motif cleavage and secretion into the cross-wall.

Data availability

All data generated or analysed during this study are included in the manuscript and supporting files. Source data files have been provided for Figure 2.

Article and author information

Author details

  1. Wenqi Yu

    Department of Microbiology, University of Chicago, Chicago, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Dominique M Missiakas

    Department of Microbiology, University of Chicago, Chicago, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Olaf Schneewind

    Department of Microbiology, University of Chicago, Chicago, United States
    For correspondence
    oschnee@bsd.uchicago.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-9652-3823

Funding

National Institute of Allergy and Infectious Diseases (AI038897)

  • Olaf Schneewind

Deutsche Forschungsgemeinschaft (YU 181/1-1)

  • Wenqi Yu

National Institute of Allergy and Infectious Diseases (AI052474)

  • Olaf Schneewind

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

Reviewing Editor

  1. E Peter Greenberg, University of Washington School of Medicine, United States

Version history

  1. Received: December 5, 2017
  2. Accepted: May 5, 2018
  3. Accepted Manuscript published: May 14, 2018 (version 1)
  4. Version of Record published: May 21, 2018 (version 2)

Copyright

© 2018, Yu 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. Wenqi Yu
  2. Dominique M Missiakas
  3. Olaf Schneewind
(2018)
Septal secretion of protein A in Staphylococcus aureus requires SecA and lipoteichoic acid synthesis
eLife 7:e34092.
https://doi.org/10.7554/eLife.34092

Share this article

https://doi.org/10.7554/eLife.34092

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