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Updated: Sep 10, 2025
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Laboratory Simulation of an IronII-rich Precambrian Marine Upwelling System to Explore the Growth of Photosynthetic Bacteria
Published on: July 24, 2016
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Microbial iron oxide respiration coupled to sulfide oxidation.
Song-Can Chen1,2,3, Xiao-Min Li4,5, Nicola Battisti6
1State Key Laboratory of Soil Pollution Control and Safety, Zhejiang University, Hangzhou, China. songcan.chen@zju.edu.cn.
Nature
|August 27, 2025
Summary
Microbes can now be recognized for linking sulfur and iron cycles by oxidizing sulfide using iron(III) oxide. This biological process is vital in anoxic environments, impacting global element cycling.
Area of Science:
- Microbiology
- Geochemistry
- Biogeochemistry
Background:
- Microorganisms drive Earth's sulfur cycle, but their full capacities and integration with other cycles are unclear.
- The coupling of sulfide oxidation with iron(III) oxide reduction was previously thought to be abiotic.
- Understanding microbial roles in elemental cycling is crucial for environmental science.
Purpose of the Study:
- To investigate microbial sulfur metabolism and its integration with iron cycling.
- To identify prokaryotes capable of coupling sulfide oxidation with iron(III) oxide reduction.
- To characterize the biological mechanism linking sulfur and iron biogeochemical cycles.
Main Methods:
- Comprehensive genomic analysis of sulfur metabolism across prokaryotes.
- Phylogenetic framework construction for sulfur transformation genes.
- Metabolic reconstructions and physiological/transcriptomic evidence from cultivated organisms.
Main Results:
- Sulfur-cycling capacity is widespread across most bacterial and archaeal phyla.
- Diverse prokaryotes were predicted to couple sulfide oxidation with iron(III) oxide respiration.
- Desulfurivibrio alkaliphilus was shown to grow autotrophically by oxidizing sulfide with iron(III) as an electron acceptor, outcompeting abiotic processes.
Conclusions:
- A novel biological mechanism links microbial sulfur oxidation and iron(III) oxide reduction in anoxic environments.
- This discovery expands the known diversity of sulfur-cycling microorganisms.
- Microorganisms play a fundamental role in linking major global element cycles.
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