Insights into AMS/PCAT transporters from biochemical and structural characterization of a double Glycine motif protease

  1. Silvia C Bobeica
  2. Shihui Dong
  3. Liujie Huo
  4. Nuria Mazo
  5. Martin Irving Harrison McLaughlin
  6. Gonzalo Jiménez-Osés
  7. Satish K Nair  Is a corresponding author
  8. Wilfred A van der Donk  Is a corresponding author
  1. University of Illinois at Urbana-Champaign, United States
  2. Universidad de La Rioja, Spain

Abstract

The secretion of peptides and proteins is essential for survival and ecological adaptation of bacteria. Dual-functional ATP-binding cassette transporters export antimicrobial or quorum signaling peptides in Gram-positive bacteria. Their substrates contain a leader sequence that is excised by an N-terminal peptidase C39 domain at a double Gly motif. We characterized the protease domain (LahT150) of a transporter from a lanthipeptide biosynthetic operon in Lachnospiraceae and demonstrate that this protease can remove the leader peptide from a diverse set of peptides. The 2.0 Å resolution crystal structure of the protease domain in complex with a covalently bound leader peptide demonstrates the basis for substrate recognition across the entire class of such transporters. The structural data also provide a model for understanding the role of leader peptide recognition in the translocation cycle, and the function of degenerate, non-functional C39-like domains (CLD) in substrate recruitment in toxin exporters in Gram-negative bacteria.

Data availability

Diffraction data has been deposited at Protein Data Bank under 6MPZ.

The following data sets were generated

Article and author information

Author details

  1. Silvia C Bobeica

    Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, United States
    Competing interests
    No competing interests declared.
  2. Shihui Dong

    Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, United States
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-1743-2163
  3. Liujie Huo

    Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, United States
    Competing interests
    No competing interests declared.
  4. Nuria Mazo

    Departamento de Química, Universidad de La Rioja, La Rioja, Spain
    Competing interests
    No competing interests declared.
  5. Martin Irving Harrison McLaughlin

    Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, United States
    Competing interests
    No competing interests declared.
  6. Gonzalo Jiménez-Osés

    Departamento de Química, Universidad de La Rioja, La Rioja, Spain
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0105-4337
  7. Satish K Nair

    Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, United States
    For correspondence
    s-nair@life.uiuc.edu
    Competing interests
    No competing interests declared.
  8. Wilfred A van der Donk

    Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, United States
    For correspondence
    vddonk@illinois.edu
    Competing interests
    Wilfred A van der Donk, Reviewing editor, eLife.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-5467-7071

Funding

National Institutes of Health (GM058822)

  • Wilfred A van der Donk

Ministerio de Economía y Competitividad (CTQ2015-70524-R)

  • Gonzalo Jiménez-Osés

National Institutes of Health (GM079038)

  • Satish K Nair

Ministerio de Economía y Competitividad (RYC-2013-14706)

  • Gonzalo Jiménez-Osés

Universidad de La Rioja (Predoctoral fellowship)

  • Nuria Mazo

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

Copyright

© 2019, Bobeica 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. Silvia C Bobeica
  2. Shihui Dong
  3. Liujie Huo
  4. Nuria Mazo
  5. Martin Irving Harrison McLaughlin
  6. Gonzalo Jiménez-Osés
  7. Satish K Nair
  8. Wilfred A van der Donk
(2019)
Insights into AMS/PCAT transporters from biochemical and structural characterization of a double Glycine motif protease
eLife 8:e42305.
https://doi.org/10.7554/eLife.42305

Share this article

https://doi.org/10.7554/eLife.42305

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