Scientists discover new 'origins of life' chemical reactions

#1
Kornee Offline
https://phys.org/news/2022-07-scientists...tions.html
https://www.nature.com/articles/s41557-022-00999-w (paywalled - but nice illustration of presumably key chemical cycle involved)
Once again, such 'breakthroughs' tend to invite more questions than answers. Always are the issues of e.g. long term survivability, poisoning, and lack of useful, biologically relevant information content in any such precursors.
I expect Tour and/or other 'debunkers' will present a strong response in due time.
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#2
C C Offline

"Now, scientists at Scripps Research have discovered a new set of chemical reactions that use cyanide, ammonia and carbon dioxide—all thought to be common on the early earth—to generate amino acids and nucleic acids, the building blocks of proteins and DNA."


Well, at first glance it just seems to be more "building blocks were widely available" news. It's long since been established that some -- if not all, of life's prebiotic ingredients can be provided by the chemical activity of even the interstellar medium and the proto-solar environment.

But apparently a new, intriguing category of processes spurs optimism that something further might fall out of this Earthly combination. Bottom line is that -- given the vastly greater volume of random chemical interactions occurring on a primordial Earth for millions of years, it seems highly unlikely that a research lab's tiny, small-scale version of such operating through mere months, years, or decades could overcome the wall of statistical odds to yield similar eventually.

However, rather than that brute approach, I guess this is a quasi-inferential approach of poking, analyzing and calculating what assembly routes can be outputted by this "new set", and if any of those can lead directly or indirectly to primitive molecular self-replication or assisted slash reciprocal replication.

Because the new reaction is relatively similar to what occurs today inside cells—except for being driven by cyanide instead of a protein—it seems more likely to be the source of early life, rather than drastically different reactions, the researchers say. [...] "What we want to do next is continue probing what kind of chemistry can emerge from this mixture," says Krishnamurthy. "Can amino acids start forming small proteins? Could one of those proteins come back and begin to act as an enzyme to make more of these amino acids?"

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#3
Kornee Offline
(Jul 29, 2022 04:49 PM)C C Wrote:

"Now, scientists at Scripps Research have discovered a new set of chemical reactions that use cyanide, ammonia and carbon dioxide—all thought to be common on the early earth—to generate amino acids and nucleic acids, the building blocks of proteins and DNA."


Well, at first glance it just seems to be more "building blocks were widely available" news. It's long since been established that some -- if not all, of life's prebiotic ingredients can be provided by the chemical activity of even and interstellar medium and the proto-solar environment.

But apparently a new, intriguing category of processes spurs optimism that something further might fall out of this Earthly combination. Bottom line is that -- given the vastly greater volume of random chemical interactions occurring on a primordial Earth for millions of years, it seems highly unlikely that a research lab's tiny, small-scale version of such operating through mere months, years, or decades could overcome the wall of statistical odds to yield similar eventually.

However, rather than that brute approach, I guess this is a quasi-inferential approach of poking, analyzing and calculating what assembly routes can be outputted by this "new set", and if any of those can lead directly or indirectly to primitive molecular self-replication or assisted slash reciprocal replication.

Because the new reaction is relatively similar to what occurs today inside cells—except for being driven by cyanide instead of a protein—it seems more likely to be the source of early life, rather than drastically different reactions, the researchers say. [...] "What we want to do next is continue probing what kind of chemistry can emerge from this mixture," says Krishnamurthy. "Can amino acids start forming small proteins? Could one of those proteins come back and begin to act as an enzyme to make more of these amino acids?"

The quoted passage ends with questions. Indicating they are groping in the dark as always. Here's the imo central 'protocell survivability' conundrum:
https://www.youtube.com/watch?v=DwAFZb8juMQ
Of course getting anywhere near an actual realistic 'protocell' replete with encapsulating membrane (but NO miraculously 'evolved' mechanism to divide and accurately reproduce) is a prodigious leap all in itself. From postulated rugged self-replicating presumably RNA-ish molecules. Hope lives eternal in the mainstream OOL community. I almost admire the faith required.
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#4
confused2 Offline
The simplest form of 'reproduction' is for a molecule to increase in length until the molecule breaks mechanically into two. The two fragments increase in length and .. there you have it.
Starting from one molecule you get an icky blob or more likely an icky film. For the film to grow it may need what is below or above the film or more likely both. The environment at the top and bottom of the film isn't the same so best strategy for growth is different. Possibly the best (winning) film results from some cooperation between inner and outer molecules. If the film formed over (say) a small grain of sand you have a mobile 'thing' which can infect more grains of sand by physical contact. I'm kind of fixated on the idea that the inside molecules might not be able to make the outside molecules and vice versa - I did once ask if 'modern' cells can make a cell membrane from scratch - to which there was no answer.
Anyway, there you have a thing with a primitive cell membrane that can get washed around by water and that is enough for today.
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#5
Kornee Offline
(Jul 30, 2022 12:57 PM)confused2 Wrote: The simplest form of 'reproduction' is for a molecule to increase in length until the molecule breaks mechanically into two. The two fragments increase in length and .. there you have it.
Starting from one molecule you get an icky blob or more likely an icky film. For the film to grow it may need what is below or above the film or more likely both. The environment at the top and bottom of the film isn't the same so best strategy for growth is different. Possibly the best (winning) film results from some cooperation between inner and outer molecules. If the film formed over (say) a small grain of sand you have a mobile 'thing' which can infect more grains of sand by physical contact. I'm kind of fixated on the idea that the inside molecules might not be able to make the outside molecules and vice versa  - I did once ask if 'modern' cells can make a cell membrane from scratch - to which there was no answer.
Anyway, there you have a thing with a primitive cell membrane that can get washed around by water and that is enough for today.
Ahh - fond memories:
https://www.imdb.com/title/tt0051418/
Eventually parachuted somewhere into an Antarctica crevasse iirc. Now if we could somehow locate it, the secret to life might be uncovered?
Or - foolishly doing so might end it all for us? Anyway the original was the best imo. Big Grin
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