Generation of long-chain fatty acids by hydrogen-driven bicarbonate reduction in ancient alkaline hydrothermal vents

The origin of life required membrane-bound compartments. Long-chain amphiphilic molecules, such as fatty acids, are strong candidates for the first cell membranes, but their generation remains unclear. This study shows that the reaction of dissolved hydrogen and bicarbonate with magnetite under conditions of continuous flow, alkaline pH, and relatively low temperatures (90 °C) generates a range of functionalised long-chain aliphatic compounds, including mixed fatty acids up to 18 carbon atoms in length. This suggests that similar chemistry in bicarbonate-rich water mixing with alkaline hydrogen-rich fluids from serpentinization could have driven the generation of readily available membrane-forming amphiphilic organic molecules in early cellular life.

Graham Purvis, Lidija Šiller, Archie Crosskey, Jupiter Vincent, Corinne Wills, Jake Sheriff, Cijo Xavier, Jon Telling