Evolution's Missing Link

   

Diamidophosphate, a molecule well known to chemists for decades, may be the secret to the beginnings of life on Earth. According to a study published in Nature Chemistry, researchers from the Scripps Research Institute "We suggest a phosphorylation chemistry that could have given rise, all in the same place, to oligonucleotides, oligopeptides, and the cell-like structures to enclose them". The formation of proteins and lipids has been explored, and is well understood, but the actual catalyst for life has evaded scientists. 

Phosphorylation is a necessary biological process, and modern phosphorylating agents are  well known and studied, such as ATP.  Many suggested primordial phosphorylating agents are not applicable to every reaction that would have needed to take place for life to begin. Many of them require uncommon reacting environments. The breakthrough of the study showed that DPA is capable of phosphoyrlating all four of the nucleoside bases required to create RNA under a wide range of conditions. DPA is also capable of phosphorylating sugars. With these new discoveries, DPA may be the molecule that scientists have been looking for for so long.

DPA's ability to not only phosphorylate nucleosides, but begin RNA synthesis was investigated by adding the catalyst Imidazole, shown above. With both of these molecules present in solution with nucleosides, short chains of RNA were synthesized. Imidazole is not guaranteed to have been present at pre-biological times, but it is plausible. While it is hard to prove what molecules were actually present 4 billion years ago, we can be relatively sure of DPA's ability to have kickstarted life, based on its presence in modern day biological molecules, and the results shown in the lab. The lead researcher of the team, Ramanarayanan Krishnamurthy, says that the next direction for the team will be collaborating with geochemists, to investigate potential sources for the molecule. 

https://www.sciencedaily.com/releases/2017/11/171106112301.htm