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Laboratory Simulation of an Iron(II)-rich Precambrian Marine Upwelling System to Explore the Growth of Photosynthetic Bacteria
Published on: July 24, 2016
Insight into the evolution of the iron oxidation pathways
Marianne Ilbert1, Violaine Bonnefoy
1Aix-Marseille Université, CNRS, BIP UMR7281,13009, Marseille, France. milbert@imm.cnrs.fr
Biochimica Et Biophysica Acta
|October 10, 2012
Summary
Dissimilatory iron (Fe(II)) oxidation is an ancient microbial metabolism. This review proposes that Fe(II) oxidation pathways evolved convergently multiple times, with different pathways emerging at distinct evolutionary stages.
Area of Science:
- Biogeochemistry
- Microbial Evolution
- Bioenergetics
Background:
- Ferrous iron (Fe(II)) was abundant in early oceans, influencing life's evolution.
- Iron is essential for life and serves as an energy source for microbes.
- Fe(II) oxidation is a widespread microbial metabolism across diverse environments.
Purpose of the Study:
- To review the evolutionary history of dissimilatory Fe(II) oxidation pathways.
- To propose a timeline for the emergence of different Fe(II) oxidation metabolisms.
- To explore the convergent evolution of iron oxidation in Bacteria and Archaea.
Main Methods:
- Analysis of iron paleochemistry.
- Phylogenetic analysis of iron-oxidizing microorganisms.
- Examination of the physiology of iron oxidizers.
- Investigation of redox protein cofactors.
Main Results:
- Dissimilatory Fe(II) oxidation is likely an ancient and convergently evolved metabolism.
- Nitrate-dependent anoxic Fe(II) oxidizers are suggested as the most ancient.
- Phototrophic anoxic and neutrophilic oxic Fe(II) oxidizers likely evolved before the Great Oxidation Event.
- Acidophilic Fe(II) oxidizers likely emerged after the rise of atmospheric oxygen.
Conclusions:
- Fe(II) oxidation pathways evolved independently multiple times.
- The timing of Fe(II) oxidation pathway evolution is linked to Earth's changing environment.
- Understanding Fe(II) oxidation offers insights into early life and bioenergetic systems.
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