Direction of Protein Biosynthesis as a Reflection of the Prebiotic Environment

Systematical analyses of the folding pathways of simple polypeptides show that for systems containingL-stereoisomers their natural tendency to be right-handed abakes when the polypeptide terminal are naturally charged. This disadvantageous effect is minimized by an introduction of charged amino acid residues into the polypeptide chain at the beginning of its synthesis. Since in the rebiotic environment negatively charged amino acids were more prominent than positively charged ones, we conclude that the fixed direction of protein biosynthesis might be a result of “a broken symmetry” of amino acid charges.