Glutathione S-transferases (GSTs) are a family of Phase II detoxification enzymes. Although they are involved in a number of biochemical processes, their main function is to protect cellular macromolecules from reactive electrophiles. They do this by catalyzing the conjugation of glutathione (GSH) to various endogenous and exogenous electrophilic compounds.
In plants, glutathione transferase protect plants from biotic and abiotic stress by isolating harmful metals and toxins such as herbicides and insecticides from the remainder of the cell.