Physical and Chemical Models for the Emergence of Biological Homochirality

Donna Blackmond examines two linked problems in the origin of life: how an initially balanced mixture of molecular mirror images could acquire a handedness bias, and how that small bias could be amplified. She compares four experimental approaches using chemical kinetics and solid–solution equilibria.

The first is asymmetric autocatalysis, including the Soai reaction and kinetic models connecting self-replication with suppression of the opposite enantiomer. Blackmond distinguishes this powerful model from a demonstrated prebiotic pathway. She then discusses amplification through eutectic partitioning and through attrition-enhanced deracemization, where dissolution, crystal growth and interconversion can produce a single-handed solid.

The final approach incorporates stereochemical selection into plausible prebiotic chemistry. Examples explore reciprocal enrichment involving sugars and amino-acid precursors. The lecture argues that accounts of how biological building blocks arose must explain their chirality alongside their synthesis.