2008/02/20 by Marcelo Gleiser, Sara Imari Walker · 2 citations
Biochemistry, Genetics and Molecular Biology · Neuroscience · Physics and Astronomy · #Origins and Evolution of Life #Photoreceptor and optogenetics research #Protein Structure and Dynamics #astro-ph #physics.chem-ph #q-bio.BM
paper · pdf · doi:10.1007/s11084-008-9134-5
published as Orig. Life Evol. Biosph. 38, 293-315 (2008)
arxiv created 2008/02/20 · openalex publication_date 2008/05/08 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/02
A generalized autocatalytic model for chiral polymerization is investigated in detail. Apart from enantiomeric cross-inhibition, the model allows for the autogenic (non-catalytic) formation of left and right-handed monomers from a substrate with reaction rates εL and εR, respectively. The spatiotemporal evolution of the net chiral asymmetry is studied for models with several values of the maximum polymer length, N. For N=2, we study the validity of the adiabatic approximation often cited in the literature. We show that the approximation obtains the correct equilibrium values of the net chirality, but fails to reproduce the short time behavior. We show also that the autogenic term in the full N=2 model behaves as a control parameter in a chiral symmetry- breaking phase transition leading to full homochirality from racemic initial conditions. We study the dynamics of the N -> infinity model with symmetric (εL = εR) autogenic formation, showing that it only achieves homochirality for ε< εc, where εc is an N-dependent critical value. For ε≤ εc we investigate the behavior of models with several values of N, showing that the net chiral asymmetry grows as tanh(N). We show that for a given symmetric autogenic reaction rate, the net chirality and the concentrations of chirally pure polymers increase with the maximum polymer length in the model. We briefly discuss the consequences of our results for the development of homochirality in prebiotic Earth and possible experimental verification of our findings.