Ionic and chiral asymmetries as physical factors of biogenesis and ontogenesis

Abstract

The proposed approach to the evolution of the universe and life on Earth is based on general physical principles that lead to the assertion that their rise was made possible through the chain of emergence and collapse of symmetries in the states of dynamic systems. The hypothesis is proposed and substantiated that the phylogenetic law of Haeckel (each species in its ontological development repeats its evolutionary history) might be extended so that it would include two processes that are comparable from the point of view of biophysics: the emergence of the discrete predecessors of the cell in the ancient Ocean and initial stages of embryogenesis. A new proposition is made and grounded that formation of the two fundamental biological asymmetries (cellular-ionic and molecular-chiral) are similar and constitute coupled bifurcations that gave rise to life on the Earth and the individual life of multicellular organisms. This work aims to resolve the principal contradiction between the notions of the essentially thermodynamic non-equilibrium nature of all living cells and conventional equilibrium models of their origination. The authors and their colleagues give the first experimental evidence that the original deviation of the predecessors of living cells from the state of thermodynamic equilibrium may be directly related to the spontaneous generation of the two fundamental biological asymmetries (ionic and molecular) in the ocean’s thin surface layer. The ionic asymmetry predefined the ability of discrete protocells to react to external stimuli, which was a necessary condition of their inclusion into the process of biological evolution, whereas the chiral asymmetry predetermined the unique molecular stereospecificity of carbon compounds in the processes of biosynthesis and metabolism. Concerning amino acids, chiral asymmetry may also be extended to embrace participation of their D-isomers in the regulation of the most important stages of ontogenesis, while earlier it was deemed only as an underpinning of the principle of the “chiral purity of the biosphere,” within which solely the inclusion of amino acid L-isomers in the ribosomal synthesis of proteins. The enantiomers of biologically important chiral substances are able to not only play a key role in complementary interaction but also serve as a logical element for switching information and not only at the level of simple coding of the “yes/no” type but also at the level of conversion of “sensible” signals.