Norvaline and Norleucine May Have Been More Abundant Protein Components during Early Stages of Cell Evolution

  title={Norvaline and Norleucine May Have Been More Abundant Protein Components during Early Stages of Cell Evolution},
  author={Claudia Alvarez-Carre{\~n}o and Arturo Becerra and Antonio Lazcano},
  journal={Origins of Life and Evolution of Biospheres},
The absence of the hydrophobic norvaline and norleucine in the inventory of protein amino acids is readdressed. The well-documented intracellular accumulation of these two amino acids results from the low-substrate specificity of the branched-chain amino acid biosynthetic enzymes that act over a number of related α-ketoacids. The lack of absolute substrate specificity of leucyl-tRNA synthase leads to a mischarged norvalyl-tRNALeu that evades the translational proofreading activites and produces… 

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  • J. C. Aledo
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    Protein science : a publication of the Protein Society
  • 2019
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