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Rationalization of Asymmetric Amplification via Autocatalysis Triggered by Isotopically Chiral Molecules.

ABSTRACT: Asymmetric amplification induced in the Soai autocatalytic reaction by chiral initiators that are enantiomeric only by virtue of an isotope, e.g., -CH₃ vs CD₃-, is examined by spectroscopic, kinetic, and DFT modeling studies to help understand requirements for the emergence of biological homochirality. We find that the initiator inhibits the autocatalytic pathway at the outset of the reaction but ultimately provides the imbalance required for asymmetric amplification. This work provides clues in the ongoing search for prebiotically plausible versions of asymmetric autocatalysis.

SUBMITTER: Hawbaker NA

PROVIDER: S-EPMC6026777 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature

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Rationalization of Asymmetric Amplification via Autocatalysis Triggered by Isotopically Chiral Molecules.

Hawbaker Neil A NA Blackmond Donna G DG

ACS central science 20180606 6

Asymmetric amplification induced in the Soai autocatalytic reaction by chiral initiators that are enantiomeric only by virtue of an isotope, e.g., -CH3 vs CD3-, is examined by spectroscopic, kinetic, and DFT modeling studies to help understand requirements for the emergence of biological homochirality. We find that the initiator inhibits the autocatalytic pathway at the outset of the reaction but ultimately provides the imbalance required for asymmetric amplification ...[more]

PMID: 29974074

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