Handedness, Origin of Life and Evolution

Abstract

Biological polymers have a preferred chirality ond can replicate themselves. Physical arguments provide insight into which of these unique and apparently related properties evolved first, and by what mechanism.

Selective adsorption ofl- andd-amino acids on calcite: Implications for biochemical homochirality

“…This phenomenon suggests that local, highly selective concentration of D-and L-enantiomers may arise along step-like features, with calcite serving as a template for linear arrays of homochiral amino acids. Such a configuration may promote homochiral polymerization (24)(25)(26), which is a key step in the synthesis of self-replicating peptides (27,28). We suggest that mineral-mediated chiral selectivity, in conjunction with homochiral polymerization, may thus provide a link between prebiotic synthesis and the RNA͞protein world.…”

Spatial dynamics of homochiralization

“…The question of the origin of life is closely connected with the question of how handedness (chirality) of living organisms came about (Avetisov et al 1991). The sugars produced in plants via photosynthesis, for example via the rather innocently looking reaction 6 CO 2 + 6 H 2 O → C 6 H 12 O 6 + 6 O 2 ,…”

An Introduction to Chirality at the Nanoscale

“…Homochiral nucleic acid polymers, for example, do not form efficiently in a racemic solution of the monomers [22]. Theoretical analysis suggested that addition of a nucleotide of the wrong handedness halts the polymerization [23], a process called enantiomeric cross-inhibition. However, homochirality in the chiral monomers is not essential for generating homochiral synthetic polymers [3].…”