Understanding the formation of fundamental biological systems not only promises to expand the frontiers of scientific understanding, but also has the potential to shed light on the nature of life by guiding the search for life beyond Earth.

How everything is arranged

If we simplify the biological structure of terrestrial organisms, it turns out that the cornerstones of life are cells, the transmission of genetic information via DNA, and metabolism mediated by protein enzymes. Traces of these basic traits can be traced back to the earliest stages of evolutionary history. Unraveling the mechanisms that contributed to the emergence of these essential biological components is important not only for scientific progress, but also for solving existential questions about the nature of life and its possible existence beyond our planet.

While these “prebiotic” studies shed light on several potential pathways for the origin of life, they cannot pinpoint a single, definitive trajectory in which life arose worldwide.

Another way involves using evolutionary biology tools to reconstruct early life forms based on predicted data from modern life forms. However, this approach is limited by the genetic remains conserved in modern organisms, which limits retrospective view.

Learn more about the new approach

Collaborative work by astrobiologists and colleagues from NASA’s Jet Propulsion Laboratory aims to systematically combine these two methodologies. They argue that combining laboratory research of possible ways of life with evolutionary reconstruction of ancient forms could potentially solve the age-old mystery of the origin of life.

The central place in their approach, studying the electron transport chain – an important aspect of modern life – from two points of view. Permeating the entire spectrum of life, from bacteria to humans, this metabolic system acts as a conduit for the production of chemical energy. The researchers found evidence of this particular metabolic strategy in early life forms and established a link between modern and primitive electron transport chains. Remarkably, they saw hints of electron transport-like chemistry in Earth-forming minerals and ocean waters.

In light of these discoveries, the scientists developed a plan to further investigate the earliest forms of electron transport chains. This new trajectory aims to deepen the understanding of the metabolism of ancient lifeforms and, more broadly, to unravel the complex web of life’s origins.

The definition of life includes qualities such as reproduction, growth, metabolism, energy absorption and response to the environment. While this classification applies to life on Earth, the possibility of life beyond our planet forces us to identify life forms that may be radically different from our usual understanding.