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Lab-made primordial soup yields RNA bases
- badloginagain 7y ago> could have made A, U, C and G (adenine, uracil, cytosine and guanine, respectively) Im kind of upset that they don't refer to it going forward as GUAC (as in guacamole)
- flmontpetit 7y agoPrimordial guac
- tmoot 7y agoYour comment made my day :)
- overcast 7y agoGUAC is always extra
- holler 7y agodarn you chipotle!
- phkahler 7y agoThe avocado industry didnt see this one coming or they probably would have paid for that change.
- proeymen 7y agowdajdhajdha
- rpmisms 7y agoWhoa. I didn't know we could do that.
- jonmc12 7y ago> Carell’s team has shown how all nucleobases could form under one set of conditions: two separate ponds that cycle through the seasons, going from wet to dry, from hot to cold, and from acidic to basic, and with chemicals occasionally flowing from one pond to the other. I've enjoyed Bruce Damer's explanation of related theory, "The Hot Spring Hypothesis for the Origin of Life". Search "goldilocks chemistry" for some helpful background and visualizations on this page - https://extendedevolutionarysynthesis.com/the-hot-spring-hypothesis-for-the-origin-of-life-and-the-extended-evolutionary-synthesis/ https://extendedevolutionarysynthesis.com/the-hot-spring-hyp...
- yarg 7y agoI was going to reply with "now do it accidentally", but that actually seems like it could be a tidally guided experiment that would occur coincidentally with a relatively high frequency.
- yarg 7y agoAnother nice thing here is that we are left with a fairly low complexity - perhaps even high accuracy super-computer simulable - mechanism by which we can draw out viable candidates for probable forms of life across a wide variety of initial environments. Which seems cool to me.
- salgernon 7y agoIs that the Brice Damer of “DigiBarn” fame (vintage computer restoration and archiving)? An illustration shows a MITS Altair reading a paper tape, presumably to illustrate interpreting dna instructions.
- tasty_freeze 7y agoYes, one and the same guy
- jamesakirk 7y agoYes, it is the same Bruce Damer! Here is a clip of Bruce giving Wozniack a tour of the DigiBarn: https://www.youtube.com/watch?v=OsHM3MXnrNM https://www.youtube.com/watch?v=OsHM3MXnrNM He's a fascinating individual who wears many hats. He's done a ton of interviews on podcasts (his own, Duncan Trussel Family Hour, Erik Davis's Expanding Mind, Future Fossils, and Rogan come to mind).
- Valmar 7y agoFor all of these lab soups, it means basically nothing. None of this has advanced any understanding of the Neo-Darwinian origin of life model. There's still no working theory of how one gets from basic building blocks to a fully-functioning working cell, nevermind the rest.
- brink 7y agoTo those downvoting this comment, can you please clarify why you're downvoting? This is also how I see it, and I'd like to know the counter-argument.
- Valmar 7y agoThe Neo-Darwinists are downvoting me, no doubt. I don't buy the Christian fairytale, either. In fact, I'm happy to accept that none of us know what the origin of life is. Life is just too complicated to be an accident of random, purposeless matter. Life is also too complex and multi-faceted to be explained by any religion's mythos.
- nurettin 7y agoIt is great that you've found a way to feel superior to others with your purpose narrative.
- aazaa 7y ago> Carell, an organic chemist, and his collaborators have now demonstrated a chemical pathway that — in principle — could have made A, U, C and G (adenine, uracil, cytosine and guanine, respectively) from basic ingredients such as water and nitrogen under conditions that would have been plausible on the early Earth. The reactions produce so much of these nucleobases that, millennium after millennium, they could have accumulated in thick crusts, Carell says. His team describes the results in Science on 3 October. > The results add credence to the ‘RNA world’ hypothesis, says Carell, who is at the Ludwig Maximilian University of Munich in Germany. ... It's worth noting that what was made were nucleobases - flat very low molecular weight molecules - that when attached to ribose yield nucleotides. It is nucleotides, not nucleobases, that form RNA. The "RNA world hypothesis" still needs to explain where the ribose came from, how it was joined with the bases that were supposedly littering the Earth's surface, and how the resulting nucleotides started spontaneously assembling themselves through combination with phosphate into polymers. That's a very, very tall order in chemistry.
- hinkley 7y agoThere's a multiverse theory that there are many possible or existing universes with different physical constants, affecting everything from chemistry to orbital mechanics, and the reason we are having this conversation is because this universe was conducive to the formation of highly organized lifeforms capable of abstract thought. In this line of reasoning "Why this set of constants" doesn't matter, because only the universes that could have observers would be observed.
- builderburg 7y agoThe anthropic principle doesn't depend on a multiverse.
- chrisshroba 7y agoNot on a multiverse directly, but I think there is merit to @hinkley's claim. Say there's a one trillionth chance that life forms on an earth-like planet. There are likely trillions of earth-like planets, so chances are good (given the assumptions) that life forms on (at least) one of those planets. People on that planet (Earth) will marvel that life was created and search for reasons that seem plausible and likely for life to have been created given the initial conditions, but the initial assumption that the chances were minuscule still remains. That is to say, we may not be able to easily predict and rationalize the beginning of life based on the initial conditions of the earth, because it is likely that it was an improbable fluke. It feels like a lottery winner trying to explain how they won the lottery.
- JorgeGT 7y agoThe actual paper: http://doi.org/10.1126/science.aax2747 http://doi.org/10.1126/science.aax2747
- pmiller2 7y agoReminds me of the Miller-Urey experiment, except Miller and Urey didn’t find amino acids that could form DNA or RNA. https://en.wikipedia.org/wiki/Miller%E2%80%93Urey_experiment https://en.wikipedia.org/wiki/Miller%E2%80%93Urey_experiment
- dsego 7y agoI remember that one from school.
- gmoot 7y agoMiller-Urey found amino acids (not nucleotides as in the current experiment), the building blocks of proteins. It's at the other end of the chicken/egg "which came first" between proteins (which catalyze cellular reactions) and DNA (information storage).
- GistNoesis 7y ago>The chemistry is also a “strong indication” that the appearance of RNA-based life was not an exceedingly lucky event, but one that is likely to happen on many other planets, he adds. Does this mean a new lower bound for the fl factor for the drake equation ?
- The_rationalist 7y agoThan why all earth living beings come from one common ancestry rather than many different ones?
- UnFleshedOne 7y agoFirst mover advantage probably. If abiogenesis is common but not too common, whatever starts reproducing first might have a few billion years to spread everywhere and take over all possible niches.
- TheRealPomax 7y agoMostly: because billions of years have passed. Even if it turns out there we millions of different self-replication mechanisms that were complex enough to give rise to (an abstract form of) competition, early Earth has a period of hundreds of millions of years in which each and everyone one of those had plenty of time to run their course to extinction. Remember that that single common ancestor was _not_ alone on the planet. They might have been millions or even hundreds of millions of other potential ancestors, but if there were, all of them died out before the start of the fossil record.
- Grue3 7y agoAt any point in time there was likely a great variety of ecological niches on Earth. It seems weird that one kind of organism would achieve total global domination. For example Bacteria and Archaea have diverged relatively early on the scale of evolution, and both of these domains have survived until the modern times without one dominating the other.
- scoopertrooper 7y ago
- miles_matthias 7y agoIf you’re looking for a good fiction read relating to this, I just finished “Origin” by Dan Brown, would recommend.
- aomega08 7y agoI am amazed by the timing. Literally finished reading the book this morning and spent most of the day deep in Wikipedia researching primordial soups.
- Gatsky 7y agoThese abiogenesis experiments are a little strange... they aim to show that something could have happened. Whether that is what actually happened is considered less relevant and in fact can probably never be determined. Does anyone really believe that it is impossible to get spontaneous nucleotide generation under certain conditions (the conditions also being speculative)? The really interesting thing would be finding nucleotides or nitrogenous bases where there isn’t life, eg on Mars or an asteroid.
- ecoled_ame 7y agoMeteorites contain nitrogenous bases https://www.pnas.org/content/108/34/13995 https://www.pnas.org/content/108/34/13995
- Gatsky 7y agoFascinating thanks, sorry I should have searched it up.
- ChuckMcM 7y agoIt is the law of large numbers. It goes with the theory that if you buy 100 billion lottery tickets you asymptotically approach 100% chance of winning. In the case of abiogenesis, if you can show that the conditions for this effect were possible, and that those conditions could persist for millions of years, the probability that the "special" one occurs, approaches 100%. It doesn't explain everything, it is just a link in the chain of things that increases our understanding of our world.
- andy_ppp 7y agoI sometimes find the chances of us being here so remote, it can't really be just survival of the fittest can it? There must be other means for evolution to be more intelligently selective. I'm arguing that you'd see some kind of evolved "invisible" hand rather than an actual maker behind all of this.
- MauranKilom 7y ago> it can't really be just survival of the fittest can it? Why not?
- outworlder 7y agoNo invisible hand is required. Any life form that has reached the cognitive capability to reason about itself will be amazed by the sheer "coincidence" of their habitat. "wow, isn't it amazing that our planet's atmosphere is composed of the very ammonia we need to survive in?" No invisible hand required. Also evolution is "intelligently selective". Surviving and reproducing is a pretty intelligent mechanism. It will find local maxima pretty effectively.
- memling 7y ago> Any life form that has reached the cognitive capability to reason about itself will be amazed by the sheer "coincidence" of their habitat. "wow, isn't it amazing that our planet's atmosphere is composed of the very ammonia we need to survive in?" Isn't this a non sequitur? Whether any life form would wonder about its existence (probable or otherwise) has no bearing whatever on whether it evolved or was designed or specially created.
- h9n 7y agoWe should not be surprised that the environment we find ourselves in is so seemingly well-suited to the flourishing of life. I believe the grandparent post was saying this as a response to the idea that things are too improbably perfectly-suited for us. Far from being a non-sequitur, it is almost stating a tautology. The environment we find ourselves in is the one that has given rise to us, with our ability to think about these things. I'm sure there is a Douglas Adams passage that illustrates this but I can't remember it.
- unexaminedlife 7y agoHas anyone proven that the "soup" has to be liquid? I'm no chemist, but I was curious one day so I looked through the chemical composition of humans, and was surprised to see that almost all of the base elements from the periodic table that we are composed of are lighter than air. Just ran the numbers again for this post: ~96.2% oxygen,hydrogen,nitrogen,carbon ~ 3.8% calcium,phosphorus, potassium,sulfur,sodium, chlorine,magnesium The highest atomic number for any of these elements is 20 (calcium), while krypton is listed on wikipedia as a "major constituent in earth's atmosphere" with an atomic number of 36. EDIT: And in fact it gets more interesting when you analyze the chemical composition of DNA / RNA.
- naniwaduni 7y ago> almost all of the base elements from the periodic table that we are composed of are lighter than air This is almost completely gibberish since you don't find atoms in isolation.
- outworlder 7y ago> This is almost completely gibberish since you don't find atoms in isolation. No you don't. You find them in molecules. Nowadays it is a bit tough to find the pure gases in our planet, but they are readily available in high quantities in our universe. In gaseous form, even.
- deleted 7y ago[deleted]
- unexaminedlife 7y agoVery interesting. That's probably another assumption that may be worth attention. Is it necessary that DNA / RNA molecules were originally formed on earth? This may not be directly relevant to this idea, but first thing that came to mind when I read your comment was this: https://en.wikipedia.org/wiki/Panspermia https://en.wikipedia.org/wiki/Panspermia
- unexaminedlife 7y ago
- joyjoyjoy 7y agoI came across an article about DNA but did not had time to read it and lost it. It was about some ideas why DNA has 4 bases (and not 6 or 8). They also mention why 20 (?) amino acids. It was something similar to degrees of freedom. Not sure where I saw it. hackernews? Might have been Scientific American. I anyone remembers I would appreciate a link.
- EForEndeavour 7y agoThis Stack Exchange thread has some fascinating answers and links to sources: https://biology.stackexchange.com/questions/2874/why-are-there-exactly-four-nucleobases-in-dna https://biology.stackexchange.com/questions/2874/why-are-the...
- david-gpu 7y agoWas it an article about how there are 64 possible encodings of 3 bases (codons), but some of them are synonymous and only 20 unique amino acids are synthetized? And how this redundant encoding appears to be unusually resistant to mutations, as replacing one base with another would often encode a chemically similar amino acid? I remember reading something like that, but I couldn't find it either.
- joyjoyjoy 7y agoNo, it argued on a mathematical basis for this.
- SomeOldThrow 7y agoThe claim is that only hydrogen, oxygen, and nitrogen are necessary for the base nucleotides, right?
- mannykannot 7y agoPlus carbon, of course.
- microcolonel 7y agoI was just having a conversation about the probabilistic craziness of abiogenesis this morning with a young christian who was out proselytizing, this is a step toward the real deal (though I think the title goes further than the research here). Glad to see chemists are still trying to answer this beautiful, burning question. To those in this thread wondering: yes, there are people so flabbergasted by abiogenesis that they turn to alternative answers.
- Roritharr 7y agoA while ago I read somewhere that the odds of life creating itself via basic chemical pathways are so miniscule, that there must be quite a few instances of mechanical clocks creating itself by rocks beating together over the aeons in the universe before the first dna based organism appeared. Might be very wrong but still a beautiful picture.
- marshray 7y agoI tend to think statements like that say more about the knowledge and passions of the writer than about the laws of the universe. The fundamental point underlying the Nature article is that we don't actually know "the odds of life creating itself via basic chemical pathways". What we do know is that life appeared on Earth quite soon after liquid water.
- justinjlynn 7y agoIndeed, the law of large numbers applied to quadrillions and quadrillions of atoms and essentially uncountable numbers of interactions between them yields a large likelihood for even very unlikely independent events. The important thing to remember is that bootstrapping means it only has to happen purely by chance a relatively small number of times - perhaps only once. It turns out that the number of rock clock trials are far, far fewer and they don't bootstrap and so it is much less likely for one to exist even if the independent probability may be much higher. Statistics is often paradoxical, but then again, that's why we have logical systems for dealing with it. We'd be much better off, as a species, if a better understanding of statistics and statistical analysis were more widely spread and valued. Dawkins's explaination in "climbing mount improbable" is a good one.
- speedplane 7y ago> the law of large numbers applied to quadrillions and quadrillions of atoms and essentially uncountable numbers of interactions between them yields a large likelihood for even very unlikely independent events It’s not so simple. If something is extremely unlikely but also has many chances to occur, the probability of the thing occurring is a very large number divided by another very large number. In these cases, it’s not always clear if the resulting probability will be high or low. Just stating that there are quadrillions of potential interactions is meaningless if the chances of any one forming something useful can range from one in a billion to one in a quadrillion quadrillion quadrillion. Much like zero divided by zero (or in this case infinity divided by infinity) the overall probability is pretty much undefined.
- deleted 7y ago[deleted]
- roland00 7y agoHow is this different from the Miller-Urey experiments from the 1950s ? I am asking this for someone who is more knowledgeable and technical than me. "To my understanding" ? Those 1952 experiments yielded 20 amino acids, and this experiment in 2016 to 2019 experiments merely are demonstrating RNA can be made with a similar experiment? Our cells naturally use RNA, specifically mRNA in a "translation" process at the Ribosomes part of our cells where the Amino Acids are used to create longer protein chains. Am I remembering my AP Biology correctly or did I get something wrong?
- pkrein 7y agoIt may not be necessary for complex organic molecules to assemble out of nothing in a finely tuned primordial soup. Two recent studies to illustrate this: 1. Simple chemical droplets can divide and multiply in the right conditions: https://arxiv.org/pdf/1603.01571v1.pdf https://arxiv.org/pdf/1603.01571v1.pdf 2. “Evolution” from that simple beginning may be enough according to the theory of dynamic kinetic stability: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3843823/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3843823/
- surfsvammel 7y agoI got extremely excited when I read the headline. Finally!, I thought. Then I read the first part: > Carell, an organic chemist, and his collaborators have now demonstrated a chemical pathway that — in principle — could have made A, U, C and G in principle, what? No! The headline implies that actual RNA had formed, spontaneously. Not in principal. Going back to arguing with Creationists.
- mannykannot 7y agoIt says RNA bases right in the title, though one has to know something about RNA's structure to appreciate its limited relevance - see aazaa's comment. The article claims the synthesis has been demonstrated, so I think that in principle is there because we do not actually know if this particular process occurred in nature.
- surfsvammel 7y agoOk. My RNA/DNA knowledge is quite limited. But I still don’t get it. Did they come up with a way it could happen, or did they actually make it happen out of the “soup”. To me—as someone who knows little about it, except for the fact that having RNA/DNA spontaneously form under these conditions would be be awesome for our understanding of our origins, and would make a killer argument when talking to creationists—the difference between the two is very significant.
- mannykannot 7y agoThe article shows that RNA bases were actually created in the lab. Furthermore, this is not the first time, but it is the first time they have all been produced by one process: Now, Carell’s team has shown how all nucleobases could form under one set of conditions: two separate ponds that cycle through the seasons, going from wet to dry, from hot to cold, and from acidic to basic, and with chemicals occasionally flowing from one pond to the other. The researchers first let simple molecules react in hot water and then allowed the resulting mix to cool down and dry up, forming a residue at the bottom that contained crystals of two organic compounds. They then added water back, and one of the compounds dissolved and was washed away into another reservoir. The absence of that water-soluble molecule allowed the other compound to undergo further reactions. The researchers then mixed the products again, and their reactions formed the nucleobases. This is progress (especially as the yield is apparently quite high), but as both azaa and the last paragraph of the article point out, we are still lacking the ribose backbone of the RNA molecule. I don't think it is possible to have a killer argument against determined creationists, as they do not regard evidence in the same way as you and I do. Any discusion with them will take the form of a whack-a-mole game.
- dmpanch 7y agoI recommend reading "Origin of life. From nebula to cell" of Michail Nikitin. Not sure if it's translated from Russian, but the book is fresh and considers many modern theories in terms of chemistry.
- lurquer 7y agoBefore inquiring whether something can be made accidentally, perhaps one should determine if it can be made intentionally. That is, can organic chemists create functioning RNA from scratch? How about a strand of DNA? (And, by scratch, I mean starting with components that were not derived from living organisms.)