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Cited by 236Origins and Evolution of LifeCO2 Reduction Techniques and CatalystsCarbon dioxide utilization in catalysis

Native iron reduces CO2 to intermediates and end-products of the acetyl-CoA pathway

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Varma, Sreejith J., Muchowska, Kamila B., Chatelain, Paul, Moran, Joseph·2018·Nature Ecology & Evolution
DOI 10.1038/s41559-018-0542-2PMC PMC5969571

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Abstract

Autotrophic theories for the origin of life propose that CO 2 was the carbon source for primordial biosynthesis. Among the six known CO 2 fixation pathways in nature, the acetyl-CoA (AcCoA; or Wood-Ljungdahl) pathway is the most ancient, and relies on transition metals for catalysis. Modern microbes that use the AcCoA pathway typically fix CO 2 with electrons from H 2, which requires complex flavin-based electron bifurcation. This presents a paradox: how could primitive metabolic systems have fixed CO 2 before the origin of proteins? Here, we show that native transition metals (Fe 0, Ni 0 and Co 0) selectively reduce CO 2 to acetate and pyruvate-the intermediates and end-products of the AcCoA pathway-in near millimolar concentrations in water over hours to days using 1-40 bar CO 2 and at temperatures from 30 to 100 °C. Geochemical CO 2 fixation from native metals could have supplied critical C 2 and C 3 metabolites before the emergence of enzymes.

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Crossref · 10.1038/s41559-018-0542-2

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  • Fe0, Ni0, Ni3Fe and silica-supported Co-Fe alloys can replace the proteins that synthesize formate, acetate, pyruvate from H2 and CO2 via the acetyl-CoA pathway.

    “Second, Fe0, Ni0, Ni3Fe and silica‐supported Co‐Fe alloys can replace the proteins that synthesize formate, acetate, pyruvate from H2 and CO2 via the acetyl‐CoA pathway [60, 61, 62, 63, 64] (Fig. 1C).”

    From Evidence for corrin biosynthesis in the last universal common ancestor (2025) · cites this paper as [61]

    The Results and discussion and Conclusions (page numbers unavailable) show that Fe0 and Ni0 promote enzyme-free CO2 fixation yielding formate, acetate and pyruvate. They do not report experiments with Ni3Fe or silica-supported Co-Fe alloys. The experiments used native metals as electron sources, not H2 as a reactant, so the stated H2-and-CO2 condition is not supported by this paper. (LLM, conf=0.88)

    Experimental — accuracy not yet measured

  • Only the acetyl-CoA pathway operates in vitro to form formate, acetate and pyruvate from H2 and CO2 without enzymes or cofactors, using only metals or minerals that occur in hydrothermal vents as catalysts.

    “Moreover, only one of those seven, again only the acetyl CoA pathway, operates in vitro to form its main products – formate, acetate and pyruvate [49, 90] – from H2 and CO2 without enzymes or cofactors, using only metals or minerals that occur in hydrothermal vents as catalysts [60, 61, 62, 63, 64, 125].”

    From Evidence for corrin biosynthesis in the last universal common ancestor (2025) · cites this paper as [61]

    The Results and discussion and Conclusions (pages not provided) report enzyme-free CO2 reduction by native metals, producing formate, acetate and pyruvate in reactions resembling the acetyl-CoA pathway. But the Methods use metals and CO2 as inputs, not H2 and CO2 with metals solely as catalysts. The paper also does not establish that this is the only pathway operating in vitro under the stated conditions. (LLM, conf=0.88)

    Experimental — accuracy not yet measured

  • Both the TCA and the WLP may have a non-enzymatic origin, testifying to their potential emergence long before LUCA.

    “In fact, both the TCA and the WLP may have a non-enzymatic origin, testifying to their potential emergence long before LUCA (Ralser 2018;Varma et al. 2018).”

    From The Emergence of Life (2019) · cites this paper as Varma et al. 2018

    The Abstract proposes prebiotic origins for the acetyl-CoA (Wood–Ljungdahl) pathway. The Results and discussion and Conclusions describe enzyme-free reactions corresponding to parts of the reductive TCA cycle and a possible prebiotic network linking the two pathways. The paper does not establish that the TCA cycle as a whole emerged non-enzymatically or date either pathway’s emergence to long before LUCA. (LLM, conf=0.78)

    Experimental — accuracy not yet measured

  • The oldest carbon fixation pathway known among organisms today, the acetyl-CoA pathway, uses H2 as an electron donor and CO2 as an electron acceptor.

    “the oldest carbon fixation pathway known among organisms today, the acetyl-CoA pathway [135,136], uses H2 as an electron donor and CO2 as an electron acceptor”

    From ‘Whole Organism’, Systems Biology, and Top-Down Criteria for Evaluating Scenarios for the Origin of Life (2021) · cites this paper as [136]

  • The fact that the oldest carbon fixation pathway known among organisms today, the acetyl-CoA pathway, uses H2 as an electron donor and CO2 as an electron acceptor, suggests that an acetyl-CoA-like pathway was present from the earliest stages.

    “The fact that the oldest carbon fixation pathway known among organisms today, the acetyl-CoA pathway, uses H2 as an electron donor and CO2 as an electron acceptor, suggests that an acetyl-CoA-like pathway was present from the earliest stages [135,136,137] (Figure 4, step 1c).”

    From ‘Whole Organism’, Systems Biology, and Top-Down Criteria for Evaluating Scenarios for the Origin of Life (2021) · cites this paper as [136]

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1 of the 53 references couldn’t be matched to a known paper.

Research works printed but not linked: 3

  1. [41]Darling DJ The Universal Book of Astronomy Wiley Hoboken, NJ 2004 260
  2. [42]Krot AN Keil K Scott ERD Goodrich CA Weisberg MK Treatise on Geochemistry second edition 2014 1 1 63
  3. [43]Russell MJ Hall AJ Mellersh AR Natural and Laboratory Simulated Thermal Geochemical Processes Springer Netherlands, Dordrecht 2003 325 388

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Authors
Varma, S. J., Muchowska, K. B., Chatelain, P., & Moran, J.
Affiliations
Centre National de la Recherche Scientifique (FR)
Corresponding author
Moran, Joseph
ORCID
Venue
Nature Ecology & Evolution
Publisher
Springer Science and Business Media LLC
Published
2018-04-23
Volume
2
Issue
6
Pages
1019-1024
ISSN
2397-334X (ISSN-L)
DOI
10.1038/s41559-018-0542-2
PMC
PMC5969571
OpenAlex
W2799784280
Cited by
235
References
53
Citations by year
2026: 20 · 2025: 22 · 2024: 34 · 2023: 26 · 2022: 35 · 2021: 27 · 2020: 23 · 2019: 26 · 2018: 22
FWCI
13.13
Type
journal article
Language
en
Open access
Licence
Locations
  • Nature Ecology & Evolution (publishedVersion)
  • bioRxiv (Cold Spring Harbor Laboratory) (acceptedVersion)
  • PubMed (publishedVersion)
  • Helmholtz Centre for Ocean Research Kiel (GEOMAR) (acceptedVersion)
  • Europe PMC (PubMed Central) (acceptedVersion)
  • PubMed Central (acceptedVersion)
Funders
  • European Commission (HORIZON2020)
  • Agence Nationale de la Recherche (ANR-10-LABX-0026)
  • Université de Strasbourg
Topics
  • Physical Sciences › Physics and Astronomy › Astronomy and Astrophysics › Origins and Evolution of Life
  • Physical Sciences › Energy › Renewable Energy, Sustainability and the Environment › CO2 Reduction Techniques and Catalysts
  • Physical Sciences › Chemical Engineering › Process Chemistry and Technology › Carbon dioxide utilization in catalysis
Keywords
acetyl-CoA pathway, CO2 fixation, native iron, metal catalysis, CO2 reduction, acetyl-CoA, origin of metabolism
MeSH terms
Acetyl Coenzyme A, Carbon Dioxide, Iron, Oxidation-Reduction

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