Did key building blocks for life come from deep space?

Did key building blocks for life come from deep space?
Surface science setup in UH Mānoa’s W.M. Keck Research Laboratory in Astrochemistry. Credit: University of Hawaii at Manoa

All living beings need cells and energy to replicate. Without these fundamental building blocks, living organisms on Earth would not be able to reproduce and would simply not exist.

Little was known about a key element in the , phosphates, until now. University of Hawaiʻi at Mānoa researchers, in collaboration with colleagues in France and Taiwan, provide compelling new evidence that this component for life was found to be generated in outer space and delivered to Earth in its first one billion years by meteorites or comets. The phosphorus compounds were then incorporated in biomolecules found in cells in living beings on Earth.

The breakthrough research is outlined in "An Interstellar Synthesis of Phosphorus Oxoacids," authored by UH Mānoa graduate student Andrew Turner, now assistant professor at the University of Pikeville, and UH Mānoa chemistry Professor Ralf Kaiser, in the September issue of Nature Communications.

According to the study, phosphates and diphosphoric acid are two major elements that are essential for these building blocks in molecular biology. They are the main constituents of chromosomes, the carriers of genetic information in which DNA is found. Together with phospholipids in cell membranes and adenosine triphosphate, which function as energy carriers in cells, they form self-replicating material present in all living organisms.

Replicating interstellar conditions

Did key building blocks for life come from deep space?
Comet 67P/Churyumov-Gerasimenko. Credit: ESA/Rosetta/NAVCAM

In an ultra-high vacuum chamber cooled down to 5 K (-450℉) in the W.M. Keck Research Laboratory in Astrochemistry at UH Mānoa, the Hawaiʻi team replicated interstellar icy grains coated with carbon dioxide and water, which are ubiquitous in cold molecular clouds, and phosphine. When exposed to ionizing radiation in the form of high-energy electrons to simulate the cosmic rays in space, multiple phosphorus oxoacids like phosphoric acid and diphosphoric acid were synthesized via non-equilibrium reactions.

"On Earth, phosphine is lethal to living beings," said Turner, lead author. "But in the , an exotic phosphine chemistry can promote rare chemical reaction pathways to initiate the formation of biorelevant molecules such as oxoacids of phosphorus, which eventually might spark the molecular evolution of life as we know it."

Kaiser added, "The phosphorus oxoacids detected in our experiments by combination of sophisticated analytics involving lasers, coupled to mass spectrometers along with gas chromatographs, might have also been formed within the ices of comets such as 67P/Churyumov-Gerasimenko, which contains a phosphorus source believed to derive from phosphine." Kaiser says these techniques can also be used to detect trace amounts of explosives and drugs.

"Since comets contain at least partially the remnants of the material of the protoplanetary disk that formed our solar system, these compounds might be traced back to the interstellar medium wherever sufficient phosphine in interstellar ices is available," said Cornelia Meinert of the University of Nice (France).

Upon delivery to Earth by meteorites or comets, these phosphorus oxoacids might have been available for Earth's prebiotic phosphorus chemistry. Hence an understanding of the facile synthesis of these oxoacids is essential to untangle the origin of water-soluble prebiotic compounds and how they might have been incorporated into organisms not only on Earth, but potentially in our universe as well.


Explore further

How phosphorus came in from the cold

More information: Andrew M. Turner et al. An interstellar synthesis of phosphorus oxoacids, Nature Communications (2018). DOI: 10.1038/s41467-018-06415-7
Journal information: Nature Communications

Citation: Did key building blocks for life come from deep space? (2018, September 27) retrieved 19 June 2019 from https://phys.org/news/2018-09-key-blocks-life-deep-space.html
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Sep 27, 2018
Ahh, a backdoor version of the panspermia tripe.

Yep, a lot of phosphorous was incorporated into the early Earth planetesimal. All that is buried nice and deep into the Earth's core.

What matters to us, since the end of the Hadaean epoch? Are all the iron-nickle rocks that have fallen onto the Earth's crust. Delivering their constitute varieties of phosphorous. Over the last few billion years.

I wouldn't be surprised if future space colonization would find the phosphorous content to be more valuable than all the other elements in IIG rocks.

Sep 28, 2018
" ... this component for life was found to be generated in outer space and delivered to Earth in its first one billion years by meteorites or comets."

"The phosphorus compounds were then incorporated in biomolecules found in cells in living beings on Earth."

Are they saying that the meteors and/or meteorites brought chemicals to allow already living cells the ability to replicate?

""But in the interstellar medium, an exotic phosphine chemistry can promote rare chemical reaction pathways to initiate the formation of biorelevant molecules such as oxoacids of phosphorus, which eventually might spark the molecular evolution of life as we know it."

Really? Interstellar medium? Fact or assumption?

Sep 28, 2018
Phosphates and other biomolecules have a multitude of sources; add one.

""But in the interstellar medium, an exotic phosphine chemistry can promote rare chemical reaction pathways to initiate the formation of biorelevant molecules such as oxoacids of phosphorus, which eventually might spark the molecular evolution of life as we know it."

Really? Interstellar medium? Fact or assumption?


The IM reaction is likely, according to the research; the rest is possible hypothesis.

Nitpick: science do not do 'assumptions', but use constraints. Dunno about the amount of phosphine, for example.

Sep 28, 2018
Why b_b_g_l, dontcha know?

Rule No. ! in any disagreement? "you" are always "constrained".
Your competitor is always the "assumption"!

Sep 30, 2018
"you" are always "constrained".
Your competitor is always the "assumption"!


It is an attempt of misdirection to start discuss opinion - or even sports: "competition" - when the claim was on science.

But of course you know that.

Sep 30, 2018
Oh tb_, I'm just trying to bring a bite of humor to enliven the dry bones of scientific pomposity.

Besides, (since YOU brought it up) think of all the physics science lessons one could learn from playing baseball or shooting pool.

And all the exciting advances in the medical sciences that are being developed out of American Football!

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