Structure of bacterial phospholipid transporter MlaFEDB with substrate bound

  1. Nicolas Coudray
  2. Georgia L Isom
  3. Mark R MacRae
  4. Mariyah N Saiduddin
  5. Gira Bhabha  Is a corresponding author
  6. Damian C Ekiert  Is a corresponding author
  1. New York University School of Medicine, United States

Abstract

In double-membraned bacteria, phospholipid transport across the cell envelope is critical to maintain the outer membrane barrier, which plays a key role in virulence and antibiotic resistance. An MCE transport system called Mla has been implicated in phospholipid trafficking and outer membrane integrity, and includes an ABC transporter, MlaFEDB. The transmembrane subunit, MlaE, has minimal sequence similarity to other transporters, and the structure of the entire inner-membrane MlaFEDB complex remains unknown. Here we report the cryo-EM structure of MlaFEDB at 3.05 Å resolution, revealing distant relationships to the LPS and MacAB transporters, as well as the eukaryotic ABCA/ABCG families. A continuous transport pathway extends from the MlaE substrate-binding site, through the channel of MlaD, and into the periplasm. Unexpectedly, two phospholipids are bound to MlaFEDB, suggesting that multiple lipid substrates may be transported each cycle. Our structure provides mechanistic insight into substrate recognition and transport by MlaFEDB.

Data availability

The model has been deposited in PDB under the accession code 6XBD and the map has been deposited in EMDB under the accession code EMD-22116. Raw data were deposited into EMPIAR (EMPIAR-10536).Plasmids generated in this study will be deposited in Addgene.

The following data sets were generated
The following previously published data sets were used

Article and author information

Author details

  1. Nicolas Coudray

    Department of Cell Biology and Applied Bioinformatics Laboratory, New York University School of Medicine, New York, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-6050-2219
  2. Georgia L Isom

    Skirball Institute, New York University School of Medicine, New York, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Mark R MacRae

    Department of Cell Biology, New York University School of Medicine, New York, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-4941-9526
  4. Mariyah N Saiduddin

    Department of Cell Biology and Department of Microbiology, New York University School of Medicine, New York, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Gira Bhabha

    Department of Cell Biology, New York University School of Medicine, New York, United States
    For correspondence
    gira.bhabha@gmail.com
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0624-6178
  6. Damian C Ekiert

    Department of Cell Biology and Department of Microbiology, New York University School of Medicine, New York, United States
    For correspondence
    damian.ekiert@EKIERTLAB.ORG
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2570-0404

Funding

National Institutes of Health (R35GM128777)

  • Damian C Ekiert

National Institutes of Health (R00GM112982)

  • Gira Bhabha

Damon Runyon Cancer Research Foundation (DFS-20-16)

  • Gira Bhabha

Pew Charitable Trusts (PEW-00033055)

  • Gira Bhabha

American Heart Association (20POST35210202)

  • Georgia L Isom

National Institutes of Health (T32 GM088118)

  • Mark R MacRae

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

Reviewing Editor

  1. Adam Frost, University of California, San Francisco, United States

Publication history

  1. Received: August 27, 2020
  2. Accepted: November 24, 2020
  3. Accepted Manuscript published: November 25, 2020 (version 1)
  4. Version of Record published: January 7, 2021 (version 2)

Copyright

© 2020, Coudray 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. Nicolas Coudray
  2. Georgia L Isom
  3. Mark R MacRae
  4. Mariyah N Saiduddin
  5. Gira Bhabha
  6. Damian C Ekiert
(2020)
Structure of bacterial phospholipid transporter MlaFEDB with substrate bound
eLife 9:e62518.
https://doi.org/10.7554/eLife.62518
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