'Fuel cell model' sheds new light on origin of life

In a path-breaking research, scientists have developed a 'fuel cell model' for developing a similar energetic process that may have led to the emergence of life on earth.

The researchers have demonstrated a proof of concept for their 'fuel cell model' of the emergence of cell metabolism on earth, a crucial biological function for all living organisms.

"What we are trying to do is to bridge the gap between the geological processes of the early earth and the emergence of biological life on this planet," said Terry Kee from University of Leeds.

All life forms use the same chemical processes that occur in a fuel cell to generate their energy, Kee added.

Fuel cells in cars generate electrical energy by reacting fuels and oxidants.

This is an example of a 'redox reaction' as one molecule loses electrons is oxidised and one molecule gains electrons is reduced.

Certain geological environments can be considered as 'environmental fuel cells' since electrical energy can be generated from redox reactions between hydrothermal fuels and seawater oxidants, such as oxygen.

"Certain minerals could have driven geological redox reactions, later leading to a biological metabolism," said Laura Barge from the journal Astrobiology.

Iron and nickel are much less reactive than platinum.

However, a small but significant power output successfully demonstrated that these metals could still generate electricity in the fuel cell - and hence also act as catalysts for redox reactions on early earth.

"With these techniques, we could actually test whether any given hydrothermal system could produce enough energy to start life, or even, provide energetic habitats where life might still exist and could be detected by future missions," she said.

The study appeared in the journal Astrobiology.