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Comment by Cannabat | Hacker News Reader

I believe submission title is inaccurate:

> This study shows that various mafic rock glasses almost certainly present on the surface of the Hadean Earth catalyze the formation of polyribonucleic acid in water starting from nucleoside triphosphates.

> Thus, the prebiotic relevance of this result very much depends on whether nucleoside triphosphates were present to Hadean impact fields.

In other words, RNA spontaneously forms on basalt lava glass in the presence of nucleoside triphosphates. These are compounds for which there is no known prebiologic formation process - we only know of nucleoside triphosphates as compounds created by living organisms.

Disclaimer: I am not an expert in this area, I just read the article.

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I trained as a biochemist and you nailed it. The submission title's claim is wildly more extraordinary than the actual result. It's like claiming "Lines of humans spontaneously appear on a hot tin roof" when what happened was "humans spontaneously link arms when placed upon a hot tin roof."

The original title is much less clickbaity ‘ Catalytic Synthesis of Polyribonucleic Acid on Prebiotic Rock Glasses’. Maybe one of the mods could change it since it’s not following the site rules anyways.

But is that original title going to properly convey significance to non-biologists/the lay audience?

Coming up with good titles that will survive the HN thoughtchamber is not easy.

The existing, clickbaity title claims a significance that doesn't exist.

Seems more reasonable a claim than life was breathed into clay to form man.

I mean, if you imagine life on earth originated as a petri dish experiment by some advanced species the whole "breathed life into clay" might not be so far fetched, given some allowance for numerous translation context changes.

You're saying scientific processes (petri dish experiment) may have created life because we can't yet explain what scientific processes may have created life? And ancient, unscientific mythological fairy tales may somehow have encoded this event, despite having always been taken at face-value up until they were scientifically and rationally disproven?

Yes, that is exactly the problem.

It is an interesting result that there is spontaneous polymerization catalyzed by volcanic rock glasses, but this is an extremely simple reaction, which is expected to happen spontaneously in various conditions.

Making the monomers, i.e. the nucleoside triphosphates, requires a long chain of complex reactions, and also energy.

There is no doubt that RNA has first appeared accidentally, by spontaneous polymerization of nucleoside triphosphates, but those must have been produced by an already existing form of life, which had to use a continuous source of energy for complex molecule synthesis, e.g. dihydrogen, carbon monoxide and a ionic concentration gradient, which can be provided by submarine vents.

While the study does not offer any new information about the actual origin of life, the first accidental synthesis of RNA must have used some catalyst and that catalyst might have been a component of volcanic rocks, as shown in this study.

Only after some molecules of RNA with random composition already existed, due to spontaneous polymerization, it could happen for a RNA molecule to serve as a template for replication, during the polymerization of another RNA molecule. Therefore it is important to determine in which conditions the polymerization of RNA can happen, in the absence of specialized enzymes.

>we only know of nucleoside triphosphates as compounds created by living organisms

That is your claim. But the article claims, and I'm not saying it's true, I also am not an expert… but it's an interesting claim:

"many proposals are emerging describing how triphosphates might have been made on the Hadean Earth"

Sure is an interesting claim. Key words include "proposals", "emerging", and "might" - sounds like we have not demonstrated any of those processes just yet, but the people who know what they are talking about think abiogenesis is possible.

In all scientific research someone comes up with a theory that proposes an idea as it emerges that might do something. It is science's job to the then test that theory to either prove or disprove it. The problem is that from my armchair quarterback role that these theories are getting submitted and then published in the media before any testing has been done. Which can be okay as maybe that will bring it to the attention of someone in a position to actually do the testing. However, it tends to come off sound like it is fact or widely accepted as true prematurely by some of the shoddy reporting

Triphosphates are like tiny "batteries". A lot of important reactions in a cell are just moving the third phosphate to another molecule to "move" the stored energy and do something useful later, or to move the third phosphate back to charge again the "battery".

So it's not expected to have a lot of charged batteries floating around. IIRC there are some non-biological process that produce triphosphates, but the amount is tiny^n. In a life-less world, is the production speed enough to make them accumulate until there the concentration is high enough for this reaction? Or they break before they can form RNA chains?

Also, IIRC there are some alternative proposal for the formation of the first RNA. All are horrible slow an inefficient. Is this new method slightly less slow and slightly more efficient?

Also not expert.. I was looking around for the precursors and found that Ribose has been detected in meteorites[1]. That seems to leave finding prebiotic sources of the nucleobases, purine and pyrimidine.[2] Seems this is known, tho haven't seen a natural catalytic pathway to combine them into a nucleoside.

Purine can be synthesized from Formamide via simple heating[3], and Formamide is common enough that it's hypothesized as an alternative to water, for a universal solvent in exobiology.[4,5]

So, easy enough! ;)

As remarked in sibling, it seems the harder step is the energetic bump up to a triphosphate.

[1] https://en.wikipedia.org/wiki/Ribose [2] https://en.wikipedia.org/wiki/Nucleobase [3] https://en.wikipedia.org/wiki/Purine#Laboratory%20synthesis [4,5] https://en.wikipedia.org/wiki/Formamide https://en.wikipedia.org/wiki/Hypothetical_types_of_biochemi...

Still pretty cool. It’s helpful to know the conditions (and therefore planetary eras, etc) that catalyzed the development of more advanced lifeforms, to the extent that it dials in a more robust understanding of how our present ecology came to be

Ok, we've used your phrasing to replace the submitted title ("RNA spontaneously forms on basalt lava glass (abundant on Earth 4.35B years ago)"). Thanks!

Surely it goes without saying that the process only happens in the presence of the right precursors?

Consider the difference between

"Spontaneous appearance of human life in sealed room" and "Spontaneous appearance of human life in a sealed room containing two humans."

You're purposely making it extra misleading with this analogy by adding "in a sealed room", and also by using an example of a process that's already well understood

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