Functional and structural characterization of an ECF-type ABC transporter for vitamin B12

  1. Joana A Santos
  2. Stephan Rempel
  3. Sandra T M Mous
  4. Cristiane T Pereira
  5. Josy ter Beek
  6. Jan-Willem de Gier
  7. Albert Guskov  Is a corresponding author
  8. Dirk Slotboom  Is a corresponding author
  1. University of Groningen, Netherlands
  2. University of Campinas, Brazil
  3. Stockholm University, Sweden

Abstract

Vitamin B12 (cobalamin) is the most complex B-type vitamin and is synthetized exclusively in a limited number of prokaryotes. Its biologically active variants contain rare organometallic bonds, which are used by enzymes in a variety of central metabolic pathways such as L-methionine synthesis and ribonucleotide reduction. Although its biosynthesis and role as co-factor are well understood, knowledge about uptake of cobalamin by prokaryotic auxotrophs is scarce. Here, we characterize a cobalamin-specific ECF-type ABC transporter from Lactobacillus delbrueckii, ECF-CbrT, and demonstrate that it mediates the specific, ATP-dependent uptake of cobalamin. We solved the crystal structure of ECF-CbrT in an apo conformation to 3.4 Å resolution. Comparison with the ECF transporter for folate (ECF-FolT2) from the same organism, reveals how the identical ECF module adjusts to interact with the different substrate binding proteins FolT2 and CbrT. ECF-CbrT is unrelated to the well-characterized B12 transporter BtuCDF, but their biochemical features indicate functional convergence.

Data availability

Diffraction data have been deposited in PDB under the accession code 6FNP.

The following data sets were generated

Article and author information

Author details

  1. Joana A Santos

    Groningen Biomolecular and Biotechnology Institute (GBB), University of Groningen, Groningen, Netherlands
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-8294-3405
  2. Stephan Rempel

    Groningen Biomolecular and Biotechnology Institute (GBB), University of Groningen, Groningen, Netherlands
    Competing interests
    The authors declare that no competing interests exist.
  3. Sandra T M Mous

    Groningen Biomolecular and Biotechnology Institute (GBB), University of Groningen, Groningen, Netherlands
    Competing interests
    The authors declare that no competing interests exist.
  4. Cristiane T Pereira

    Institute of Biology, University of Campinas, Sao Paulo, Brazil
    Competing interests
    The authors declare that no competing interests exist.
  5. Josy ter Beek

    Groningen Biomolecular and Biotechnology Institute (GBB), University of Groningen, Groningen, Netherlands
    Competing interests
    The authors declare that no competing interests exist.
  6. Jan-Willem de Gier

    Department of Biochemistry and Biophysics, Stockholm University, Stockholm, Sweden
    Competing interests
    The authors declare that no competing interests exist.
  7. Albert Guskov

    Groningen Biomolecular and Biotechnology Institute (GBB), University of Groningen, Groningen, Netherlands
    For correspondence
    a.guskov@rug.nl
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2340-2216
  8. Dirk Slotboom

    Groningen Biomolecular and Biotechnology Institute (GBB), University of Groningen, Groningen, Netherlands
    For correspondence
    d.j.slotboom@rug.nl
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-5804-9689

Funding

Nederlandse Organisatie voor Wetenschappelijk Onderzoek

  • Josy ter Beek
  • Albert Guskov
  • Dirk Slotboom

European Molecular Biology Organization

  • Joana A Santos
  • Stephan Rempel

Horizon 2020 Framework Programme

  • Dirk Slotboom

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

Reviewing Editor

  1. José D Faraldo-Gómez, National Heart, Lung and Blood Institute, National Institutes of Health, United States

Version history

  1. Received: February 9, 2018
  2. Accepted: May 26, 2018
  3. Accepted Manuscript published: May 29, 2018 (version 1)
  4. Version of Record published: June 12, 2018 (version 2)

Copyright

© 2018, Santos 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. Joana A Santos
  2. Stephan Rempel
  3. Sandra T M Mous
  4. Cristiane T Pereira
  5. Josy ter Beek
  6. Jan-Willem de Gier
  7. Albert Guskov
  8. Dirk Slotboom
(2018)
Functional and structural characterization of an ECF-type ABC transporter for vitamin B12
eLife 7:e35828.
https://doi.org/10.7554/eLife.35828

Share this article

https://doi.org/10.7554/eLife.35828

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