Biophysicists have shown that the heat moving through rock fissures may have been responsible for the conditions that led to the development of life. Life is intricate, and this complexity extends to the processes that occur within cells. Proteins must be continuously produced, cell walls constructed, and DNA replicated. All of this can only happen if the right reaction partners come together at the right time and in high enough concentrations, while also being shielded from disruption by other substances. Evolution has fine-tuned these mechanisms over billions of years to ensure the crucial processes continue.Highly efficient processes occur at the correct place.
Four billion years ago, circumstances were likely very chaotic as prebiotic reactions laid the groundwork for the emergence of the first lifeforms. These reactions required the ‘right’ substances to come together at the ‘right’ time in one place, allowing for the formation of more complex biomolecules such as RNA and amino acid chains. While these reactions can be recreated in a laboratory with manual intermediate steps, it is extremely challenging for them to naturally occur in a simple ‘primordial soup’ environment.
Scientists have long wondered how the conditions for the origin of life on Earth came about. Researchers in the field of biophysics, led by Dr. Christof Mast and Professor Dieter Braun, along with geoscience Professor Bettina Scheu, have proposed a new idea. They suggest that the simple flow of heat could have played a crucial role in creating the right environment for the first prebiotic reactions. Their findings have been published in the journal Nature. This research sheds light on how the chaotic chemical mix of early Earth could have been transformed into the building blocks of life through the influence of heat from geological and chemical sources.
The ancient processes likely involved widespread heat flows, possibly through thin cracks filled with water. When heat flows through these cracks, it causes water convection and directs the movement of dissolved molecules along the heat flow. This combination of convection and thermophoresis leads to the accumulation and selective up-concentration of various solutes in different locations.
Ingredients for life: A pinch of this and a sprinkle of that
Mast’s group has conducted experiments to demonstrate this selective accumulation for overIn a recent study, researchers discovered that there are 60 different prebiotic building blocks, including nucleobases and amino acids, that exhibit varying thermophoresis and enrich differently in rock fissures. The lead author of the study, Thomas Matreux, explained that in a system of interconnected cracks and fissures in the rock, this effect is reinforced and results in mixtures with different compositions of prebiotic substances in each fissure. This means that simple heat flows can create a wide range of potential starting conditions for prebiotic chemistry, even from an initially uniformly dilute and unreactive solution.The study’s other lead author, Paula Aikkila, added that without the help of modern lab technology or the advanced reaction mechanisms of life today, nature could have potentially created a ‘molecular kitchen’ in large geological network systems. In this environment, all the ingredients of life would have been sorted and ready. As part of the Collaborative Research Centre “Molecular Evolution in Prebiotic Environments” (CRC 392), the researchers now plan to explore how many ‘dishes’ of life can be ‘prepared’ in this system.
Journal Reference:
- Thomas Matreux, Paula Aikkila, Bettina Scheu, Dieter BrChristof B. Mast and his team published a paper titled “Heat flows enrich prebiotic building blocks and enhance their reactivity” in the journal Nature in 2024. The DOI for the article is 10.1038/s41586-024-07193-7.