Evolutionary advantage of symmetry-breaking in primordial autocatalytic heteropolymers
Year: 2016
Type: preprint
Abstract: The macromolecules that encode and translate information in living systems exhibit distinctive structural asymmetries, including homochirality or mirror image asymmetry and 3'-5' directionality, that are invariant across all life forms. The evolutionary dynamics that led to these broken symmetries remain unknown. Using a computational model of hypothetical self-replicating autocatalytic heteropolymers, we identify a fundamental symmetry-breaking mechanism that significantly increases the rate of replication of asymmetric heteropolymers, compared to their symmetric counterparts. This broken-symmetry property, called asymmetric cooperativity, arises when the catalytic influence of inter-strand bonds on their left and right neighbors is unequal. We provide experimental evidence suggestive of its presence in DNA. Asymmetric cooperativity is used to explain, apart from the broken symmetries mentioned above, a number of other properties of DNA that includes four nucleotide alphabet, three nucleotide codons, helicity, anti-parallel double-strand orientation, heteromolecular base-pairing, asymmetric base compositions, and palindromic instability.
Source: arXiv (Cornell University)
Institution: Moffitt Cancer Center
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2346815474