Origins of Life and Evolution of Biospheres

, Volume 36, Issue 5, pp 559–565

Primordia Vita. Deconvolution from Modern Sequences.

  • Edward N. Trifonov
  • Idan Gabdank
  • Danny Barash
  • Yehoshua Sobolevsky
Article

DOI: 10.1007/s11084-006-9042-5

Cite this article as:
Trifonov, E.N., Gabdank, I., Barash, D. et al. Orig Life Evol Biosph (2006) 36: 559. doi:10.1007/s11084-006-9042-5

Abstract

Evolution of the triplet code is reconstructed on the basis of consensus temporal order of appearance of amino acids. Several important predictions are confirmed by computational sequence analyses. The earliest amino acids, alanine and glycine, have been encoded by GCC and GGC codons, as today. They were succeeded, respectively, by A- and G-series of amino acids, encoded by pyrimidine-central and purine-central codons. The length of the earliest proteins is estimated to be 6–7 residues. The earliest mRNAs were short G+C-rich molecules. These short sequences could have formed hairpins. This is confirmed by analysis of modern prokaryotic mRNA sequences. Predominant size of detected ancient hairpins also corresponds to 6–7 amino acids, as above. Vestiges of last common ancestor can be found in extant proteins in form of entirely conserved short sequences of size six to nine residues present in all or almost all sequenced prokaryotic proteomes (omnipresent motifs). The functions of the topmost conserved octamers are not involved in the basic elementary syntheses. This suggests an initial abiotic supply of amino acids, bases and sugars.

Keywords

abiotic synthesis ancient binary alphabet of proteins earliest mini-genes earliest mRNA earliest proteins evolution of triplet code last common ancestor origin of life reconstruction of ancient sequences 

Copyright information

© Springer Science+Business Media, B.V. 2006

Authors and Affiliations

  • Edward N. Trifonov
    • 1
  • Idan Gabdank
    • 2
  • Danny Barash
    • 1
    • 2
  • Yehoshua Sobolevsky
    • 1
  1. 1.Genome Diversity Center, Institute of EvolutionUniversity of HaifaHaifaIsrael
  2. 2.Department of Computer ScienceBen Gurion University of the NegevBe’er ShevaIsrael