New insight into the pyruvate decarboxylase-catalysed formation of lactaldehyde from H–D exchange experiments: a ‘water proof’ active site

Abstract

Pyruvate decarboxylase from Saccharomyces cerevisiae catalyses the formation of lactaldehyde from sodium glyoxylate and acetaldehyde. By using deuteriated sodium glyoxylate (sodium [2-²H]glyoxylate monohydrate) as a substrate it was verified that the lactaldehyde formed retains the deuterium atom. The implications of the observed result for the enzyme mechanism are discussed in the light of conclusions derived from recent molecular modelling studies.