Water-air interfaces in rock pores helped spawn life on Earth, study suggests

By Brooks Hays
Water-air interfaces encouraged the prebiotic chemical evolution that made the emergence of life possible, according to a new study. Photo by Pixabay/CC
Water-air interfaces encouraged the prebiotic chemical evolution that made the emergence of life possible, according to a new study. Photo by Pixabay/CC

July 29 (UPI) -- Before life could begin on Earth, a series of physical chemistry processes needed to occur. According to a new study, the geochemical qualities of water-air interfaces found inside tiny rock pores made this "prebiotic" chemical evolution possible.

Through a series of lab experiments, scientists in Germany detailed the physical and chemical qualities found among the water-air interfaces located inside the pores that populate volcanic rocks. Researchers found the gas-filled bubbles formed within these tiny spaces produce a unique combination of physical and chemical effects.


Before the first cells could be assembled, the first informational molecules, able to replicate, needed to be organized. Authors of the latest study determined the unique qualities of volcanic rock pores could have accelerated this organizational process.

In their new paper, published Monday in the journal Nature Chemistry, scientists described the effects of tiny bubbles on chemical reactions. When a temperature difference exists on a bubble, water usually evaporates on the warmer side and condenses on the cooler side.

"In principle, this process can be repeated ad infinitum, since the water continuously cycles between the gaseous and the liquid phase," Dieter Braun, professor of systems biophysics at the Ludwig Maximilian University of Munich, said in a news release.


The phenomenon results in the rapid accumulation of molecules on the warm side of the bubble. To better understand the phenomenon and the underlying chemical mechanisms, researchers observed chemical reaction rates under a range of circumstances.

Scientists found the mechanism is surprisingly robust, capable of producing even large concentrations of small molecules on the warm side of the bubble.

"We then tested a whole range of physical and chemical processes, which must have played a central role in the origin of life -- and all of them were markedly accelerated or made possible at all under the conditions prevailing at the air-water interface," said LMU doctoral student Matthias Morasch.

The new study built on previous research by LMU scientists that showed the physicochemical processes that encourage polymer formation are encouraged by the conditions found within liquid-gas interfaces.

During the most recent phase of experiments, scientists found when they supplied the interface with the right supply of chemicals, molecules could be accumulated at high concentrations within lipid membranes.

"The vesicles produced in this way are not perfect," Morasch said. "But the finding nevertheless suggests how the first rudimentary protocells and their outer membranes might have been formed."

According to the study's authors, their findings complement those of another study that showed temperature differences within aqueous environs can accelerate chemical reaction rates and the concentration of molecules.


"Our explanatory model enables both effects to be combined, which would enhance the concentrating effect and thus increase the efficiency of prebiotic processes," Braun said.

Latest Headlines