Is there abiotic way of mononucleotide polymerization?

Submitted by kappusha t3_1047lki in askscience

Could phosphodiester bond occur spontaneously without any enzymes in vitro or in nature between nucleoside monophosphates(which can be already produced abiotically if I'm not mistaken)? Or maybe this reaction requires some extreme conditions that we don't know about? I think it has a profound relevance to the RNA world hypothesis

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Xilon-Diguus t1_j39cewg wrote

Yes, we polymerize nucleotides abiotically all the time wiki. Remember that it is energetically favorable, the enzyme is just positioning things in the right general location.

When things start to get to a certain length we start stitching things together, but that is more of a practical solution than any sort of biochemical limit.

The RNA world hypothesis accounts for this, you are really just researching if you think that it is likely to have happened that way at this point.

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kappusha OP t1_j3aoruq wrote

My question is could it happen in prebiotic world without any enzymes?

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Xilon-Diguus t1_j3bvllg wrote

Yes, as a general rule if it can happen with an enzyme it can happen without an enzyme, enzymes just help things along.

The actual formation of nucleotides is a little more tricky, as that requires energy from the environment. Then you start to delve into deviations from the Miller-Urey experiment and arguments on what is more likely to have happened.

For RNA world to be true, you need to get catalytic activity from a simple repeating molecule, and if that molecule can actually form spontaneously is much more of a question of chance then actual chemical limitations.

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kappusha OP t1_j3cx6yt wrote

>Yes, as a general rule if it can happen with an enzyme it can happen without an enzyme, enzymes just help things along.

As far as I know it can happen between only nucleoside triphosphates, but not between nucleoside monophosphate. And nucleoside monophosphate can't become nucleoside triphosphates without enzymes abiotically. If I'm wrong correct me.

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Xilon-Diguus t1_j3degrc wrote

Yes, they can form abiotically and spontaneously, it just requires energy input from the environment (ie heat) at some stage. Also, keep in mind that diphosphates also have energetically favorable dephosphorylation reactions, they just do not work for the biotic enzyme for DNA synthesis.

If you get too deep down this rabbit hole you are going to need a chemist to answer your questions, but here is a review of how the field currently thinks it may have happened.

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