Yes, in principle. But note that the genetic code of earthly living beings seems to have been formed in strict coevolution with metabolic pathways: according to the Self-Referential Model (SRM), starting from the Glycine-Serine Cycle then followed by gluconeogenesis; the other amino acids come from glucose catabolism. The prebiotic amino acids cited in the question are considered to have possibly contributed to formation of proto-codes, which may have started a 'learning' period of prebiotic nucleopeptidic interactions. Please see more in the last dataset added to the publications of Romeu Guimarães. At your orders, I remain. http://www.icb.ufmg.br/labs/lbem/pdf/GMRTgeneticodeNov12.pdf

In my stepwise model for the origin of the genetic code (Thermosynthesis as energy source for the RNA world. Biosystems 82 (2008) 93-102) there would not necessarily have to be a relation between the amino acid concatenated and the triplet code. The genetic code would be a frozen accident, as proposed by Crick in 1968. Hence the genetic code would not have to be universal.

The idea of non-universality seems easy to test by making artificial transfer RNAs by modifying existing transfer RNAs, and observe the composition of newly translated proteins. Maybe the exp has already been done?

As it is, the code is not universal even on Earth; mitochondria use a code that is different for one codon, if I remember it well.

OK, no strict need for universality. The question is how to generate a code: models have to make sense with biology, that is, with protein sequences, functions, amino acid supply, and so forth. If, as you say of your model, "there would not necessarily have to be a relation between the amino acid concatenated and the triplet code", then what would be the use of a genetic code? At your orders, I remain.

My model for the emergence of the genetic code goes like this (you can find it the mentioned paper in Biosystems (publication year is 2005, not 2008 - sorry): the First Protein made use of thermal cycling as an energy source; in its enzymatic cavity it condensed all kind of substrates during thermal cycling, yielding not only elongated peptides but also some polyphosphates such as RNA. In the library of peptides produced in this manner, a very very small fraction had itself this capability of condensing substrates during thermal cycling such as the First Protein could. The formed RNAs could however copy themselves; they could also activate amino acids so that these easily reacted with each other. These RNAs were selected. Next these RNAs acquired the capability to recognize each other, using the acquired arms in these nascent tRNAs. The recognition led to an enhanced synthesis of the sequence required for the enzymatic cleft of the First Protein. These nascent tRNAs further evolved, so that they could recognize an extension from the first tRNA, and produced the First Protein. The extension RNA broke off, and turned into the first messenger RNA.

The use of the genetic code would therefore have been to order the translation of a first messenger RNA so that the First Protein with the right aa sequence was produced.

Hope this clarifies. Again, look at my Biosystems paper (vol 82 2005 pp 93-102), especially figs 5 and 6.

If you still have questions, please do not hesitate to ask them.

Is there any evidence on the characters of the first proteins, e. g., size, composition, activities etc, that could be checked against real proteins in data banks? In the self-referential model, a chronology was developed that predicted the first two amino acids Gly and Ser. Since Ser is not abundant prebiotically, a search was made for biosynthesis pathways and (luckily) it was found, the Glycine-Serine Cycle. Consequences of the prediction are very interesting for biology and biochemistry. Let's see how the progress goes. Thanks for your interest.

A model exists for the origin of the genetic code

devised by Jean Lehmann and Albert J. Libchaber.

Their idea is that the first tRNAs were able to bind

to any amino acid. Due to different reaction speeds of

the amino acids specific codons evolve. As far as I

understand the association between a codon and

an amino acid arises by chance and is stabilized

later.

http://phys.org/news168875229.html

http://www.plosone.org/article/info:doi/10.1371/journal.pone.0005773

@Anthonie Muller:

http://www.newscientist.com/article/dn9087-variations-in-the-genetic-code-of-life.html

https://www.researchgate.net/publication/7160422_Parallel_evolution_of_the_genetic_code_in_arthropod_mitochondrial_genomes

Further literature:

https://www.researchgate.net/publication/7687260_Evolution_of_the_genetic_triplet_code_via_two_types_of_doublet_codons

http://www.biologydirect.com/content/3/1/16

http://www.eurekalert.org/pub_releases/2010-04/si-tp040910.php

http://www.nature.com/nature/journal/v420/n6917/full/nature01185.html

http://scienceblog.com/8568/scientists-crack-dna-puzzle-point-to-hot-soup-at-origin-of-life/

http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0072225

http://www.eurekalert.org/pub_releases/2010-04/si-tp040910.php

http://phys.org/news/2013-08-insight-genetic-code.html

http://arxiv.org/abs/0904.0402

http://arxiv.org/abs/1304.3381

Regards,

Joachim

Article Abascal F, Posada D, Knight RD, Zardoya R. Parallel Evolutio...

Article Evolution of the Genetic Triplet Code via Two Types of Doublet Codons