Synthesis of activated pyrimidine ribonucleotides...

[TheFlyingBastard]

So I mentioned this paper to someone in order to support that it is in fact possible for RNA to form on its own without intelligent intervention. You know the study I'm talking about.

Someone then butted in and said:

The nucleotides were formed by mixing chemical precursors. The nucleotides were then subjected to a kind of "cyclical" dehydration/hydration process, that built up the nucleotides into RNA molecules. They did not produce functional RNA at all. In fact they have produced entire vats of RNA synthetically and still have not produced RNA that actually form function. The only way to get biological function into the RNA is for chemist to assemble it in advance.

Meaningful biological, information would be a genetic sequence for example, not just a string of built up nucleotides, there are numerous sequences that have zero biological function. Random RNA molecules not only need to self reproduce, but they need an inverted copy of themselves to do so. Biological information is the arrangement of BASES (which has nothing to do with physics or chemistry). It has everything to do with a code that produces integrated functional parts.

This is new information to me and I'm not so advanced that I can make out everything the paper itself is saying.
How relevant is what this person says exactly?

 

[Memeticemetic]

So I mentioned this paper to someone in order to support that it is in fact possible for RNA to form on its own without intelligent intervention. You know the study I'm talking about.

Someone then butted in and said:

The nucleotides were formed by mixing chemical precursors. The nucleotides were then subjected to a kind of "cyclical" dehydration/hydration process, that built up the nucleotides into RNA molecules. They did not produce functional RNA at all. In fact they have produced entire vats of RNA synthetically and still have not produced RNA that actually form function. The only way to get biological function into the RNA is for chemist to assemble it in advance.

Meaningful biological, information would be a genetic sequence for example, not just a string of built up nucleotides, there are numerous sequences that have zero biological function. Random RNA molecules not only need to self reproduce, but they need an inverted copy of themselves to do so. Biological information is the arrangement of BASES (which has nothing to do with physics or chemistry). It has everything to do with a code that produces integrated functional parts.

This is new information to me and I'm not so advanced that I can make out everything the paper itself is saying.
How relevant is what this person says exactly?

The paper itself sails right the hell over my head entirely. So, for all I know the first paragraph of his response may carry some relevant objections. His second paragraph, however, is gibberish. It appears he is attempting to shoe horn his god into the equation as that ephemeral concept, "information". A bit more specific than you usually see since he's expanded it to "meaningful biological information". Apparently he thinks that how BASES?(as in base pairs?) are arranged has nothing to do with physics or chemistry but I'll be damned if I can parse any meaning from that sentence. Ask him what the hell he's talking about when it comes to information and you may have a lulz worthy conversation a brewin'.

 

[ExeFBM]

I've skimmed through the paper, and it looks like he hasn't really understood it either. The cyclical dehydration/rehydration is just wrong. I guess he saw the -H2O / +H2O and assumed that was what was happening, but it just shows water leaving or entering the molecule and doesn't require any specific conditions. The paper is only showing the path of the green arrows, as the blue path was previously proposed, but has problems, so in any case only condensation reactions are occurring and there's no cyclical process.

As for the construction of functional RNA, that's just a matter of time. With a random assembly of nitrogenous bases it might look like it will take millions of years to get something that works, but when you realise the numbers of combinations that can be constructed simultaneously it's far more plausible. Avogadro's number gives some indication of how many molecules can be combined in a small puddle, and all you need is one combination to produce something that vaguely increases it's replication rate, and suddenly it's taken over the population, and there will be trillions and trillions more variants on that molecule.

 

[Undeath]

Technically, the study you're linking to is only half the story. It's pretty well established that activated nucleotides can polymerise and form RNA (as ExeFBM points out), but a major hurdle in abiogenesis is finding out how activated nucleotides are formed in the first place. This paper describes a way to synthesise one of the nucleotides, and in conditions that could plausibly be found in the primordial soup. However, the purpose of this study is not to address how to form RNA from the reaction mixture.
As such, the objection regarding the cyclical hydration/dehydration to form RNA has no relevance to this particular study. Having gone through their methods, I cannot find any mention of such a method, unless the objection is in regards to the purification of the compounds for analysis.

In fact they have produced entire vats of RNA synthetically and still have not produced RNA that actually form function.

Beyond the fact that these authors haven't attempted this, the statement is false. I'll have to dig around when I get home to see if I can find the article, but I'm quite sure it has been reported that a ~70 nucleotide string is sufficient to generate a replicating system. Moreover, recent findings have shown that such a string would actually be stable to the average mutation rate. In other words, once such a strand is formed, it can rapidly dominate the population, as ExeFBM says. Granted, generating one specific string of that length is extremely unlikely, but many of the positions can be varied and still produce something that works just enough. And as ExeFBM says: we're not talking about one single instance, there will be many strings being formed at once.

Meaningful biological, information would be a genetic sequence for example, not just a string of built up nucleotides, there are numerous sequences that have zero biological function. Random RNA molecules not only need to self reproduce, but they need an inverted copy of themselves to do so.

It's true that many nucleotide strings appear to be unfunctional in a biological sense, and it's true that RNA (and DNA) can only replicated by base pairing, forming the inverted strand of the one being copied. But the key here is that the process can copy the forward and reverse versions alternately, so you only need one or the other strand to get replication going for both strands.

Apparently he thinks that how BASES?(as in base pairs?)

Just wanted to point out that actually the term "bases" is correct here: RNA, especially the catalytic type, will typically be single stranded, and thus there won't be base pairs as such (although the information will be copied by base pairing). Still, you're completely correct that the function of any such sequence of bases is extremely dependent on physics and chemistry. RNA is different from DNA in that it can not only serve as a carrier of information, by forming two-stranded systems, but can also perform a chemical function, and thus the "integrated functional parts" produced from the code ARE the code itself.

In short, most of the objections have no relevance to that particular article, and the article only supports part of your argument. However, most of the objection appears to be false.


I hope some of that made sense to someone other than me :?