16 thoughts on “RNA Bootstrapping”

  1. For the longest damn time they were focused on life originating in areas exposed to air. (Which has always seemed quite odd to me.)

    But when you get into the statistical rates of the plausible random reactions, both gaseous collisions and surface-air interactions are swamped by what can occur in solution – particularly if you’re thinking of right at the mouth of an undersea vent. The high pressure and strong energy source should innately lead to combinations that are simply energetically unlikely to happen in a surface pool. Even a surface pool struck by lightening.

  2. RNA proved too unstable to work with

    Exactly, and the implications? Any experiment designed to produce RNA destroys it even faster. Anything is possible, but this is a rock rolling up hill.

    As the researchers watched, errors caused DNA self-replication to slow

    Exactly what you’d expect. How does this support any conclusion about RNA? How did this DNA replicate without RNA?

    The world is a huge place and time was no real issue

    Yup. Hold your breath and miracles will happen. Entropy can be reversed in isolated cases. But if there is any useful definition for impossible, this is it.

  3. Exactly, and the implications? Any experiment designed to produce RNA destroys it even faster. Anything is possible, but this is a rock rolling up hill.

    It’s a big limitation of the experiment, but the principle remains sound. The stuff that replicates better survives better.

    Yup. Hold your breath and miracles will happen. Entropy can be reversed in isolated cases. But if there is any useful definition for impossible, this is it.

    Keep in mind we can “hold our breath” for hundreds of millions of years here. Over that sort of span of time, miracles not only become expected, but reoccur frequently.

  4. I’ll give you 14 billion years. The problem is the entropy reverse has to happen so many times that if that isn’t the definitely of impossible, then it’s true… nothing is impossible.

  5. Just guessing, but the strict thermo definition would seem to fit Ken’s thinking.

    The entropy of a jar packed with individual amino acids is higher than that same jar with the same amino acids – but linked into a chain.

    I think the problem with that argument is that you actually need to consider the Gibbs free energy as well. I don’t have the numbers in front of me (and this isn’t my field), but I think that amino acids in chains are quite a bit more stable than free-floating amino acids in solution. That is: even though they are “more ordered”, they are also fundamentally the low point on the energy curves.

    Essentially the same reason you get diamonds. Crystals are inherently less entropic than anamorphic solids. But when the pressure and temperature conditions favor one form over another you do get order from chaos. It still doesn’t come close to bending the Three Laws: You didn’t win, you didn’t break even, and you still shouldn’t consider playing this game.

  6. Crystals are inherently less entropic than anamorphic solids. But when the pressure and temperature conditions favor one form over another you do get order from chaos.

    Exactly. Boltzmann be damned. Probability is great, but only when you have no other tool available.

  7. Ken, what exact definition of entropy do you think is reversing?

    RNA exists in a highly protected environment, the cell. Take away that cell and it deteriorates.

    amino acids in chains are quite a bit more stable than free-floating amino acids

    While true is a minor issue if the RNA itself ceases to exist.

  8. The problem is the entropy reverse has to happen so many times that if that isn’t the definition of impossible, then it’s true… nothing is impossible.

    Entropy isn’t reversed for the entire system here. You got to remember that this is all powered off the Sun which generates vast amounts of entropy through fusion and the radiating of that energy into space. Even the little sliver that intersects the Earth is more than ample to offset any local reversal of entropy that occurs.

  9. The problem is local Karl. In every experiment since the first, whatever setup they use to produce amino acids is destructive and they have to be removed or cease to exist. This local entropy is regardless of the energy source. Yes, you briefly counter entropy locally then immediately it reasserts itself. It would be like a gas self organizing into one corner of a room instead of spreading out. It’s a bridge too far.

  10. For those that think it’s just a matter of time… how many billions of years would you need for a gas to self organize into one corner of a room? Would it ever happen?

  11. For those that think it’s just a matter of time… how many billions of years would you need for a gas to self organize into one corner of a room? Would it ever happen?

    If we consider each gas molecule to be occuring at an independent random point in the room, the chance they are all in the same 1/2 of the room would be (1/2)^(number of molecules). You couldn’t even write this probability down without using scientific notation for the exponent.

  12. Ken, you’re arguing entropy, but the key ingredient is still the energy surface.

    Back to diamonds; they’re sufficiently more stable (read: strong low point on the energy surface) that even though they are pretty much a minimal entropy state (read: disfavored in the extreme on the entropy front) they are stable at low temperatures and pressures for millennia. The surface of any diamond you can actually hold is spontaneously converting to graphite at all times. But the barrier between the two states makes introconversion quite difficult without loads of energy floating around. And thus ridiculously slow under normal conditions.

    RNA/DNA/Amino acid chains aren’t so stable. At room temperatures and pressures – without the supportive environment of the cell. (As you noted.)

    But like I mentioned back in the first post, most experiments on forming amino acids have assumed that the reaction is being kicked off basically at sea-level. The first experiments were purely gas-phase – mainly because it is easy. Moving on from there has added solid-gas interactions and some solution chemistry.

    But maintaining extreme pressures or temperatures during the attempts isn’t something I’ve read any articles on as yet. As far as I can see they’re still focusing on trying to determine atmospheric concentrations and trace chemicals as potential catalysts.

    But if you believe (as I do) that the chemistry is much richer at the openings of underwater vents, experiments recreating the potential are much more expensive – and thus more rare.

  13. Oh, and I can make the vast majority of the gas in the room end up in a quite tight ball quite quickly. (At least, on geologic/astronomic scales.)

    1m x 1m x 1m aluminum box at 300 C filled with pure mercury. Press start. Time passes. Done.

    The box cools to the point that the gas wants to be (mostly) a liquid. Mercury has a very strong tendency to agglomerate. Each droplet is going to be in equilibrium with the vapor state, but the largest drop has the lowest surface-to-volume ratio. This should result in the largest drop growing to be all of the liquid-state mercury in the box.

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