Weak neutral current and β radiolysis effects on the origin of biomolecular chirality

Abstract

The possibility of a connection between the parity non-conserving weak interactions and the handedness of biomolecules has received recent attention¹. Although the asymmetric effects of the weak interactions in molecules have been estimated to be very small^2–9, Kondepudi and Nelson (KN)^10–13 have shown that autocatalytic chemical systems that spontaneously break chiral symmetry^14–19 can effectively amplify systematic chiral perturbations as small as those produced by weak neutral currents^2–4,20, despite the simultaneous presence of larger randomly fluctuating chiral perturbations, and hence provide a mechanism for producing the observed homochirality of biomolecules. I show here, in the light of new estimates of the asymmetric decomposition of racemic mixtures by β radiation⁹, that the chiral selection parameter due to β radiolysis can be up to six orders of magnitude larger than that resulting from weak neutral currents. This suggests that β radiolysis is more likely to be the selector of biomolecular chirality than weak neutral currents.