Víctor Rivilla & his colleagues at the Spanish Astrobiology Centre in Madrid have made an astonishing discovery. The team identified a vital component of the simplest phospholipid in space. If you don’t know, phospholipids are molecules that made up of the membranes of all cells on Earth. In a pre-publication that has not been peer reviewed, the team explains their discovery of the phospholipid component, known as ethanolamine, and notes that this discovery indicates that all of the precursors for life may be from the space.
Science has yet to provide full disclosure on the origin of life, but there are a few things we do know. We know that life on Earth began around 4.5 billion years ago and has involved countless molecular components. A theory explains that these components were available on earth, because the planet was sown from space with the building blocks necessary for life – this space is full of gas & dust containing all the organic molecules necessary for life.
Astronomers have observed & recorded these building blocks, which include amino acids, protein precursors, & molecules capable of storing information in the form of DNA. But there is another pivotal component for life: molecules that can form membranes capable of encapsulating & protecting molecules of life in compartments called protocells. Phospholipids have never been observed in space. Until Rivilla & his team discovery.
The origin of life on earth and on other planets
The team analyzed the light from an interstellar cloud of gas & dust called Sagittarius B2, just 390 light years from the center of Milky Way Galaxy. Ethanolmine has chemical formula NH2CH2CH2OH. The team simulated the spectrum that this molecule is expected to produce at the low temperatures believed to exist in the cloud. They then searched for & found clear evidence of this spectrum in the light that had passed through cloud. “This has important implications not only for theories about the origin of life on Earth, but also for other habitable planets & satellites anywhere in the Universe,” the team said.
Previously, astronomers had found ethanolamine in meteorites. Researchers don’t yet know how it got there, with some claiming it only formed through a strange series of reactions on a parent asteroid.
However, according to latest finding, ethanolamine is much more prevasive.
The secrecy never ends
On Earth, ethanolamine forms hydrophilic head of phospholipid molecules that self-assemble into cell membranes. Rivilla & colleagues told Astronomy Magazine that its discovery in interstellar clouds suggests that “ethanolamine may have been transferred from the proto solar nebula to planetesimals & minor bodies of solar system, and later to our planet. This, in turn, may have led to the formation of cells in prebiotic soup from which our earliest ancestors emerged.
Another radical idea is that ethanolamine could allow formation of protocells in interstellar medium itself. The interstellar medium is rich in other prebiotic components, such as water & amino acids. The result would then be ready-made melting pots of prebiotic goop able to seed the planet earth or the other body that passes by.
While none of these answer the question of how life began on Earth, the work indicates that there is no longer a mystery about where building blocks of life could have come from. “These results indicate that ethanolamine forms efficiently in space and, if delivered to early Earth, may have contributed to the assembly & early evolution of primitive membranes,” said Rivilla & the team. That said, what happened next is still shrouded’ in secrecy.