Discovery in space of ethanolamine, the simplest phospholipid head group.
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A molecule that may have been key to the emergence of life on Earth could have come from interstellar space by hitching a lift on meteorites.
The emergence of life required a molecular method of encoding and replicating genetic information. It also needed a membrane-like material to enclose and protect the genetic material.
All cell membranes today are formed from a bilayer of phospholipids, which consist of a hydrophilic headgroup and two hydrophobic tails. The simplest phospholipids incorporate the molecule ethanolamine in their headgroup.
Now, a team led by researchers at the Spanish National Research Council has shown that ethanolamine can form in interstellar space. By analysing radio telescope data, the team detected ethanolamine in an interstellar molecular cloud.
As ethanolamine has previously been detected in meteoritic material, the molecule may have been delivered to early Earth by meteorites. It could thus have been available for the formation of the first cellular membranes.
- PNAS 118, e2101314118 (2021). doi: 10.1073/pnas.2101314118