Selenocyanate derived Se-incorporation into the Nitrogenase Fe protein cluster

  1. Trixia M Buscagan  Is a corresponding author
  2. Jens T Kaiser
  3. Douglas C Rees  Is a corresponding author
  1. Howard Hughes Medical Institute, California Institute of Technology, United States
  2. California Institute of Technology, United States

Abstract

The nitrogenase Fe protein mediates ATP-dependent electron transfer to the nitrogenase MoFe protein during nitrogen fixation, in addition to catalyzing MoFe protein independent substrate (CO2) reduction and facilitating MoFe protein metallocluster biosynthesis. The precise role(s) of the Fe protein Fe4S4 cluster in some of these processes remains ill-defined. Herein, we report crystallographic data demonstrating ATP-dependent chalcogenide exchange at the Fe4S4 cluster of the nitrogenase Fe protein when potassium selenocyanate is used as the selenium source, an unexpected result as the Fe protein cluster is not traditionally perceived as a site of substrate binding within nitrogenase. The observed chalcogenide exchange illustrates that this Fe4S4 cluster is capable of core substitution reactions under certain conditions, adding to the Fe protein's repertoire of unique properties.

Data availability

Diffraction data have been deposited in the RCSB PDB under the accession codes 7TPW, 7TPX, 7TPY, 7TPZ, 7T4H, 7TQ0, 7TQ9, 7TQC, 7TNE, 7TQE, 7TQF, 7TPN, 7TQH, 7TQI, 7TPO, 7TQJ, 7TQK, and 7TPV.

The following data sets were generated

Article and author information

Author details

  1. Trixia M Buscagan

    Division of Chemistry and Chemical Engineering, Howard Hughes Medical Institute, California Institute of Technology, Pasadena, United States
    For correspondence
    tbuscaga@caltech.edu
    Competing interests
    The authors declare that no competing interests exist.
  2. Jens T Kaiser

    Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-5948-5212
  3. Douglas C Rees

    Division of Chemistry and Chemical Engineering, Howard Hughes Medical Institute, California Institute of Technology, Pasadena, United States
    For correspondence
    dcrees@caltech.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-4073-1185

Funding

Howard Hughes Medical Institute

  • Douglas C Rees

National Institutes of Health (GM45162)

  • Douglas C Rees

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

Reviewing Editor

  1. Amie K Boal, Pennsylvania State University, United States

Publication history

  1. Received: April 6, 2022
  2. Accepted: July 28, 2022
  3. Accepted Manuscript published: July 29, 2022 (version 1)

Copyright

© 2022, Buscagan 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. Trixia M Buscagan
  2. Jens T Kaiser
  3. Douglas C Rees
(2022)
Selenocyanate derived Se-incorporation into the Nitrogenase Fe protein cluster
eLife 11:e79311.
https://doi.org/10.7554/eLife.79311

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