An origin-of-life reactor to simulate alkaline hydrothermal vents

Area of Science:

• Biochemistry
• Geochemistry
• Astrobiology

Background:

• Chemiosmotic coupling, the process of harnessing proton gradients for ATP synthesis, is fundamental to all known life.
• This universal mechanism suggests ancient origins, but its precise beginnings remain unclear.
• Alkaline hydrothermal vents on early Earth possessed natural proton gradients and catalytic minerals, offering a potential environment for life's origin.

Purpose of the Study:

• To investigate the abiotic origins of chemiosmotic coupling and early biochemistry.
• To explore whether conditions in alkaline hydrothermal vents could have driven organic synthesis.
• To test the hypothesis that inorganic vent structures could prefigure the origins of life.

Main Methods:

• Construction and testing of a novel electrochemical reactor simulating alkaline hydrothermal vent conditions.
• Precipitation of thin-walled, inorganic structures containing nickel-doped mackinawite (a catalytic Fe(Ni)S mineral).
• Analysis of organic molecule generation and concentration within simulated vent structures under open-flow conditions.

Main Results:

• Simulated vent structures successfully generated low yields of simple organic molecules.
• The synthetic microporous matrices concentrated organic molecules via thermophoresis.
• The inorganic structures mimicked catalytic cofactors found in modern metabolic enzymes.

Conclusions:

• Abiotic chemistry within alkaline hydrothermal vents could have initiated key biochemical processes.
• Natural proton gradients and catalytic minerals in vents may have driven early organic synthesis.
• This research provides empirical support for hydrothermal vent theories on the origin of life.