Glyoxalase-based toolbox for the enantioselective synthesis of α-hydroxy carboxylic acids.

We report highly enantioselective synthesis of L-α-hydroxy carboxylic acids (L-αHCAs) enzymatic intramolecular Cannizzaro reaction of (hetero)aryl glyoxals in the presence of glutathione-independent human glyoxalase DJ-1. Combined with the optimized synthesis of D-αHCAs using glyoxalases I and II, this approach offers a general, scalable and operationally simple access to both enantiomers of α-hydroxy acids in moderate to excellent yields with uniformly high enantioselectivity.

A continuous spectrophotometric assay for glutathione-independent glyoxalases.

We developed a novel continuous assay to quantitatively characterize the catalytic activity of type III methylglyoxalases, a family of enzymes that detoxify methylglyoxal. This assay is based on spectrophotometric detection of hemithioacetal which forms in the reversible reaction of methylglyoxal with dithiothreitol. Due to rapid interconversion between hemithioacetal and methylglyoxal and the known equilibrium constant, hemithioacetal can be quantified spectrophotometrically at 286 nm and used as a reporter for methylglyoxal.