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I just came across this abstract:

Aminoacyl-tRNA synthetases (aaRSs) are responsible for creating the pool of correctly charged aminoacyl-tRNAs that are necessary for the translation of genetic information (mRNA) by the ribosome. Each aaRS belongs to either one of only two classes with two different mechanisms of aminoacylation, making use of either the 29OH (Class I) or the 39OH (Class II) of the terminal A76 of the tRNA and approaching the tRNA either from the minor groove (29OH) or the major groove (39OH). Here, an asymmetric pattern typical of differentiation is uncovered in the partition of the codon repertoire, as defined by the mechanism of aminoacylation of each corresponding tRNA. This pattern can be reproduced in a unique cascade of successive binary decisions that progressively reduces codon ambiguity. The deduced order of differentiation is manifestly driven by the reduction of translation errors. A simple rule can be defined, decoding each codon sequence in its binary class, thereby providing both the code and the key to decode it. Assuming that the partition into two mechanisms of tRNA aminoacylation is a relic that dates back to the invention of the genetic code in the RNA World, a model for the assignment of amino acids in the codon table can be derived. The model implies that the stop codon was always there, as the codon whose tRNA cannot be charged with any amino acid, and makes the prediction of an ultimate differentiation step, which is found to correspond to the codon assignment of the 22nd amino acid pyrrolysine in archaebacteria.

Granted, this is a few years old, but I often find myself having to admit that "I don't know" when at the root of discussions on evolution. That is, once abiogenesis has occurred, we can go on and explain the rich diversity of life, but sadly we really don't know much before that critical step. Generally, those satisfied with "magic" as an answer posit their myths and fables, whereas I'd rather try to actually find out what happened. Sadly, as the abstract shows, you actually need a level of education to understand papers such as this that is generally well beyond those who would deny the reality of evolution.

Does anyone have a collection of papers on abiogenesis that are more accessible and understandable to laypeople?

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up vote 14 down vote accepted

The fascinating field of abiogenesis is, as Nick Lane put it, "a wild west of ideas, theories, speculations, and even data". The stories we have involve a plethora of assumptions, there is no hypothesis where all or most of the pieces would fit together. Usually scientists agree it was RNA that played central role in the process, as the molecule could both carry the genetic code, necessary for hereditary natural selection, and catalyze basic biochemical reactions. Where the energy came from and how it was harnessed to maintain RNA (a rather unstable molecule) and perform work is still debated. A fermentation in a 'primordial soup' or a primitive form of respiration, perhaps through a thin iron-sulphur membrane, have been proposed as possibilities. The second gave a start to the iron-sulphur world hypothesis. Iron-sulphur minerals could catalyse the first organic reactions to synthetize sugars, amino-acids and nucleotides, and eventually RNA world, where natural selection could take over. Theories abound.

Usually reviews will give you a sound and approachable picture of the current thought on the matter. Take a look into Nick Lane's book and these articles, too.

  1. Lane N., Origin of Life in: Power, Sex, Suicide: Mitochondria and the Meaning of Life. Oxford University Press, 2005. p. 94-104.

  2. Russell, Michael (2006). First Life. American Scientist 94 (1):32.

  3. Van Noorden R., RNA world easier to make - Ingenious chemistry shows how nucleotides may have formed in the primordial soup. Nature 2009

  4. Check Hayden E. A never-ending dance of RNA - The recreation of life's origins comes a self-catalysing step closer. Nature 2009.

  5. Cech TR. Exploring the New RNA World. Nobel Prize articles

  6. Müller UF. Re-creating an RNA world. Cell Mol Life Sci. 2006 Jun;63(11):1278-93.

  7. Lazcano A, Miller SL. The origin and early evolution of life: prebiotic chemistry, the pre-RNA world, and time. Cell. 1996 Jun 14;85(6):793-8.

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+1 - great reference list. –  Richard Smith Feb 1 '12 at 12:27
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