Plant nitrilase: a new job for an old enzyme.

Nitrilases are versatile enzymes that hydrolyze nitriles to carboxylic acids and ammonia, but many members of this family lack defined biological functions. In plants, nitrilases have been associated with detoxification of cyanide-containing compounds and auxin biosynthesis; however, recent work suggests that the chemical versatility of these proteins contributes to metabolite repair. In this issue of the Biochemical Journal, Niehaus et al. demonstrate that the Nit1 nitrilase from Arabidopsis thaliana functions as a metabolite repair enzyme that removes deaminated glutathione from the cytoplasm and plastids.