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> So there must have already existed an equivalent of a bacteria, with metabolism using energy from the environment (i.e. dihydrogen with carbon dioxide and ion

> So there must have already existed an equivalent of a bacteria, with metabolism using energy from the environment (i.e. dihydrogen with carbon dioxide and ionic gradients), which was already able to make ATP, which would have been needed to synthesize the polymers made by condensation, e.g. peptides. The apparition of the first RNA virus was an initially undesirable side-effect of using ATP to perform polymer condensations. No, you're not postulating an RNA world here. The whole point of the RNA world (aka "RNA first") hypothesis is that the first life (self-contained, self-replicating particles) was RNA-based, and both proteins and lipid bilayers came later. If you argue that the first RNA was a virus that parasitized already existing organisms, then it's usually called a "metabolism first" hypothesis.

adrian_b 5y ago
Yes, that is exactly that what I have said. While there was replicating RNA before any DNA and before any proteins made by translation from RNA, metabolism must have existed before any RNA and catalysis must have been done with peptides produced by other ways than translation from RNA (today there still are such non-ribosomal peptides). Speaking about a RNA world is correct only in this sense, because RNA could not have performed any function before a mechanism for its replication had appeared and such a mechanism could not appear in any environment where ATP and the other nucleotides did not already exist. ATP and the other nucleotides could not be made without an already functioning metabolism. On the other hand, there is absolutely no need of RNA or of any other memory molecule for a working metabolism. These precedence relations are as certain as 2 + 2 = 4, so speaking of any other kind of RNA world is senseless, despite the fact that there have been indeed many publications that fail to mention why the appearance of RNA before ATP and before metabolism is impossible.
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- TchoBeer 5y ago
  >such a mechanism could not appear in any environment where ATP and the other nucleotides did not already exist. What evidence is there that this is true
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adrian_b 5y ago

Yes, that is exactly that what I have said. While there was replicating RNA before any DNA and before any proteins made by translation from RNA, metabolism must have existed before any RNA and catalysis must have been done with peptides produced by other ways than translation from RNA (today there still are such non-ribosomal peptides). Speaking about a RNA world is correct only in this sense, because RNA could not have performed any function before a mechanism for its replication had appeared and such a mechanism could not appear in any environment where ATP and the other nucleotides did not already exist. ATP and the other nucleotides could not be made without an already functioning metabolism. On the other hand, there is absolutely no need of RNA or of any other memory molecule for a working metabolism. These precedence relations are as certain as 2 + 2 = 4, so speaking of any other kind of RNA world is senseless, despite the fact that there have been indeed many publications that fail to mention why the appearance of RNA before ATP and before metabolism is impossible.

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TchoBeer 5y ago
>such a mechanism could not appear in any environment where ATP and the other nucleotides did not already exist. What evidence is there that this is true
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