Unveiling the role of inorganic nanoparticles in Earth’s biochemical evolution through electron transfer dynamics

Summary This article explores the intricate interplay between inorganic nanoparticles and Earth’s biochemical history, with a focus on their electron transfer properties. It reveals how iron oxide and sulfide nanoparticles, as examples of inorganic nanoparticles, exhibit oxidoreductase activity similar to proteins. Termed “life fossil oxidoreductases," these inorganic enzymes influence redox reactions, detoxification processes, and nutrient cycling in early Earth environments. By emphasizing the structural configuration of nanoparticles and their electron conformation, including oxygen defects and metal vacancies, especially electron hopping, the article provides a foundation for understanding inorganic enzyme mechanisms. This approach, rooted in physics, underscores that life’s origin and evolution are governed by electron transfer principles within the framework of chemical equilibrium. Today, these nanoparticles serve as vital biocatalysts in natural ecosystems, participating in critical reactions for ecosystem health. The research highlights their enduring impact on Earth’s history, shaping ecosystems and interacting with protein metal centers through shared electron transfer dynamics, offering insights into early life processes and adaptations.


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The formation of dissolved O2 in 100 mM H2O2 solution containing various iron oxide nanomaterials (10 μg/mL), measured by using a specific oxygen electrode on a multiparameter analyzer (JPSJ-606L, Leici China).The total volume of the mixture was 5 mL.All reactions were carried out in deoxygenated water at 37℃.

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The number of hydroxyl groups on the surface of various iron oxide nanomaterials measured by acid-base titration 7 is positively correlated with their corresponding catalase-like activity (expressed by the rate of dissolved oxygen generation).Reprinted with permission from Ref. 14 .Copyright © 2018 ACS C. The basic structural motif consist of a central FeO4 tetrahedra with 12 FeO6 octahedra.The hexagonal unit cell for Ferrihydrite, Fe-oxo-Fe bridge at the edge-shared octahedra 16 .The The bonded atoms (yellow) define a cubane-like moiety that connects the basic structural motif of the model.
D. The Fe-Fe distance and linkage of octahedra in Fe(III) oxides 6,17 Reprinted with permission from Ref 6 , Copyright © 2003, John Wiley and Sons E. Crystal structures of magnetite, maghemite and hematite, Reproduced from Ref. 18 with permission from the Royal Society of Chemistry(RSC).Reprinted with permission from Ref. 34 , Copyright © 2022, Elsevier

Fig 5 .
Fig 5. Intrinsic Oxidoreductase Activity of Biogenic Iron Oxide Nanoparticles

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Fig 8: Dynamic Metal Architecture of Iron Oxide Nanoparticles in the Environment

Fig 10 :Fig 11 .
Fig 10: Structural Modulation of Biogenic Iron Oxide Nanoparticles by Fungi and Implications for POD Activity

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Fig 12. Structure and Electronic Property of Three Iron Sulfides Nanoparticles

Fig 16 .
Fig 16.Natural Iron Nanoparticles in the Earth Environments A. Proposed mechanism of the POD-like activity of nanomaterials in three steps.Eb,1, Eb,2, and Eb,3 are the energy barriers; Er,1, Er,2, and Er,3 are the corresponding reaction energies.