Synthesizing Nucleic Acids Before The Emergence Of Life
Life on Earth comes in many diverse forms, yet there are certain biological molecules that are used by all life, appearing in every living cell throughout history.
It is thought that these compounds must have been present on the early Earth in order to allow for the emergence of life on our planet. How these compounds came to exist on the early Earth is a critical step in the origin of life as we know it, and could also be critical for life’s potential on other worlds.
A team of NASA-supported scientists have provided new information on how one class of biomolecule, nucleic acids, could have formed outside of living cells with the help of naturally occurring minerals in the environment before life’s emergence on Earth.
Nucleic acids are large polymers (long chains of molecules) that carry the genetic code in living cells. Two main classes of nucleic acids are deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). These biopolymers play an essential role in all cells and viruses throughout the history of the Earth.
Today, nucleic acids are synthesized inside cells. In the new study, the team of researchers studied whether or not naturally occurring minerals could have helped to build these polymers without the presence of life.
They examined a variety of minerals and showed that several could promote the synthesis and elongation in a broader set of environments than previously thought. Similar processes and environments might have also enabled the synthesis of other biological molecules necessary for life’s emergence.
The study, “Mineral-Mediated Oligoribonucleotide Condensation: Broadening the Scope of Prebiotic Possibilities on the Early Earth,” was published in the journal Life. (open access)
Astrobiology
