Scientists at the University of Newcastle, with support from the UK Natural Environment Research Council, are investigating the mystery of the emergence of life on Earth more than 3.5 billion years ago.

They investigated the transformation of inert geological materials into the first living systems. Their experiments involved a combination of hydrogen, bicarbonate, and iron-rich magnetite under conditions similar to mild hydrothermal vents. As a result of this process, many organic molecules were formed, especially fatty acids with 18 carbon atoms.

Published in magazine Contact Earth and Environment The findings potentially show how some of the basic molecules needed to create life are made from inorganic chemicals, which is important for understanding a key stage in the formation of life on Earth billions of years ago. Their findings may provide a plausible genesis for the organic molecules that formed ancient cell membranes that may have been selectively selected by early biochemical processes on early Earth.

Fatty acids in the early stages of life

Fatty acids are long organic molecules with regions that both attract and repel water, automatically forming cell-like compartments in water, and such molecules may have formed the first cell membranes. But despite their importance, it was unclear where these fatty acids came from in the early stages of life. One idea is that hot water may have formed in hydrothermal vents, where it mixed with hydrogen-rich fluids from underwater sources and mixed with CO-containing seawater.₂.

The group recreated important aspects of the chemical environment found in the early Earth oceans and the mixing of hot alkaline water from specific types of hydrothermal vents in their laboratory. They found that hot hydrogen-rich liquids, when mixed with carbon dioxide-rich water in the presence of iron-based minerals present on the early Earth, formed the types of molecules needed to form primitive cell membranes.

Lead author Dr Graham Purvis carried out research at Newcastle University and is currently a research fellow at Durham University.

He said: “Central to the origin of life are cellular compartments that are crucial for isolating internal chemistry from the external environment. These compartments played an important role in directing life-sustaining reactions, concentrating chemicals and facilitating energy production, potentially serving as the cornerstone of the first moments of life.” .

The results suggest that the convergence of hydrogen-rich fluids from alkaline hydrothermal vents with bicarbonate-rich waters on iron-based minerals may have led to the formation of rudimentary early cell membranes early in life. This process may have led to the emergence of various types of membranes; some of these could potentially serve as the cradle of life when life is just beginning. “In addition, this transformation process may contribute to the formation of specific acids found in the elemental composition of meteorites.”

Biogeochemistry lecturer and principal investigator at the Faculty of Environmental Sciences, Dr. John Telling added:

“We believe this work may be the first step into how life arose on our planet. Research is ongoing in our laboratory to determine the second important step; how these organic molecules, which initially “stick” to mineral surfaces, can rise to form spherical membrane-bound cellular compartments; the first potential to give rise to the first cellular life.” “protocells.”

Intriguingly, the researchers suggest that membrane-forming reactions like these may still occur today in oceans beneath the surface of icy moons in our solar system. This raises the possibility of an alternative origin of life on these distant worlds.