Posted by: Dan | September 20, 2007

Energy Flow at the Origin of Life

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Popular hypotheses on the origin of life generally surround the priming by hereditary material, by partitioning by micelles, or by early metabolic cycling. In Beginnings of Cellular Life, Harold Morowitz argues a sort of combination between the latter two, connecting the physical chemistries of carbon fixation, properties of C, O, H, N, P, and S, and extremely specific array of small (<500Da) organic molecules found in today’s cells. The result is a concise and potentially testable series of reactions that could have set up proto-cell membranes and the first non-equilibrium reactions. And all it would rely upon is Morowitz’s specialty – energy flow – and materials for acid-base and/or ox-redux reactions… basic chemistry.

To be sure, this book presents just a hypothesis. It is also probably over the heads of the average layperson. But his “principle of continuity” is the sound logic that any serious discussion on the origin of life must stick to, dismissing even Jacques Monod’s vision of the origin of life as an event that has happened in the past and is truly unique, such that it cannot be recreated in the lab (Chance and Necessity, 1971). Simply put, the origin of life is at least conceptually accessible to science, and therefore any relevant hypothesis must be falsifiable (or conversely, verifiable).

And as far as scientifically-argued explanations for the origin of life go, Morowitz has raised the bar, and having read the book, I’m surprised that this book has not gotten more publicity.


Responses

  1. I’ll have to check it out. I must admit that I’m skeptical of the of the metabolism first theory of abiogenesis. You need information in order for selection to be meaningful. But I’ll see what Morowitz has to say.

  2. True – that’s the glaring gap in Morowitz’s argument – while he notes that the genetic code maps nicely onto the synthesis pathways for 16 out of the 20 amino acids, he doesn’t explicitly connect his ideas on proto-cells to the RNA World or other hypotheses of later steps in biogenesis.

    Still, I can’t quite see how you could get to nucleic acids without the concentration of organic molecules (metabolic intermediates or otherwise) in proto-cells.

  3. […] may have been like, and even the pre-RNA World proto-cell? On this, Morowitz has more to say in Beginnings of Cellular Life: If one considers all low molecular weight compounds (fewer than 500 daltons) that can be made from […]


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