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A Thermodynamic Model for Water Activity and Redox Potential in Evolution and Development.
1Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring, Ministry of Education, School of Geosciences and Info-Physics, Central South University, Changsha, 410083, China. jeff@chnosz.net.
Journal of Molecular Evolution
|March 13, 2022
Summary
This study analyzes protein chemistry to track Earth's oxygen and water evolution. It reveals changes in carbon oxidation and hydration states, linking them to major geobiological events and organismal development.
Area of Science:
- Geochemistry
- Biochemistry
- Evolutionary Biology
Background:
- Geological and biological processes fundamentally involve water and oxygen.
- Understanding life's environmental interactions requires monitoring these elements across evolutionary timescales.
- Chemical transformations are key to evolution and development.
Purpose of the Study:
- To analyze chemical metrics of proteins to understand geobiological evolution.
- To infer thermodynamic parameters like oxygen fugacity and water activity.
- To decipher the evolutionary and developmental dynamics of chemical variables.
Main Methods:
- Two-stage analysis of phylostratigraphic and proteomic data.
- Obtaining chemical metrics (carbon oxidation state, stoichiometric hydration state) from protein elemental compositions.
- Modeling protein stabilities to infer thermodynamic parameters (oxygen fugacity, water activity, virtual redox potential).
Main Results:
- A rise in protein carbon oxidation state during the Great Oxidation Event.
- An increase in virtual redox potential coinciding with aerobic metabolism emergence.
- Decreasing protein hydration states during biofilm and fruit fly development.
Conclusions:
- Evolutionary and developmental changes in chemical variables can be tracked through thermodynamic protein analysis.
- Protein chemistry provides insights into Earth's geobiological history and life's adaptation.
- Thermodynamic analysis of proteins as chemical entities offers a novel approach to studying life's evolution.
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