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Cited by 56Metalloenzymes and iron-sulfur proteinsAmmonia Synthesis and Nitrogen ReductionEnzyme Structure and Function

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Structural insights into the iron nitrogenase complex

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Schmidt, Frederik V., Schulz, Luca, Zarzycki, Jan, Prinz, Simone, Oehlmann, Niels N., Erb, Tobias J., Rebelein, Johannes G.·2024·Nature Structural & Molecular Biology
DOI 10.1038/s41594-023-01124-2PMC PMC10803253

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Abstract

Nitrogenases are best known for catalyzing the reduction of dinitrogen to ammonia at a complex metallic cofactor. Recently, nitrogenases were shown to reduce carbon dioxide (CO 2 ) and carbon monoxide to hydrocarbons, offering a pathway to recycle carbon waste into hydrocarbon products. Among the three nitrogenase isozymes, the iron nitrogenase has the highest wild-type activity for the reduction of CO 2 , but the molecular architecture facilitating these activities has remained unknown. Here, we report a 2.35-Å cryogenic electron microscopy structure of the ADP·AlF 3 -stabilized iron nitrogenase complex from Rhodobacter capsulatus , revealing an [Fe 8 S 9 C - ( R )-homocitrate] cluster in the active site. The enzyme complex suggests that the iron nitrogenase G subunit is involved in cluster stabilization and substrate channeling and confers specificity between nitrogenase reductase and catalytic component proteins. Moreover, the structure highlights a different interface between the two catalytic halves of the iron and the molybdenum nitrogenase, potentially influencing the intrasubunit ‘communication’ and thus the nitrogenase mechanism.

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Metadata

Authors
Schmidt, F. V., Schulz, L., Zarzycki, J., Prinz, S., Oehlmann, N. N., Erb, T. J., & Rebelein, J. G.
Affiliations
  • Max Planck Institute for Terrestrial Microbiology (DE)
  • Max Planck Institute of Biophysics (DE)
Corresponding author
Rebelein, Johannes G.
ORCID
Venue
Nature Structural & Molecular Biology
Publisher
Springer Science and Business Media LLC
Published
2023-12-07
Volume
31
Issue
1
Pages
150-158
ISSN
  • 1545-9985 (ISSN-L)
  • 1545-9993
DOI
10.1038/s41594-023-01124-2
PMC
PMC10803253
OpenAlex
W4389440024
Cited by
56
References
1
Citations by year
2026: 14 · 2025: 19 · 2024: 20 · 2023: 3
FWCI
2.67
Type
journal article
Language
en
Open access
Licence
Locations
  • Nature Structural & Molecular Biology (publishedVersion, cc-by)
  • bioRxiv (Cold Spring Harbor Laboratory) (acceptedVersion, cc-by-nc-nd)
  • PubMed Central (publishedVersion, cc-by)
  • PubMed (publishedVersion)
Funders
  • Verband der Chemischen Industrie
  • Joachim Herz Stiftung
  • Deutsche Forschungsgemeinschaft (446841743)
  • Max-Planck-Gesellschaft
Topics
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Biochemistry › Metalloenzymes and iron-sulfur proteins
  • Physical Sciences › Chemical Engineering › Catalysis › Ammonia Synthesis and Nitrogen Reduction
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Structural Biology › Enzyme Structure and Function
Keywords
iron nitrogenase, Rhodobacter capsulatus, CO2 reduction, nitrogenase reductase, substrate channeling, molybdenum nitrogenase, enzyme mechanism, cryo-EM structure
MeSH terms
Carbon Dioxide, Hydrocarbons, Iron, Nitrogenase, Oxidation-Reduction

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