ABSTRACT
A diverse group of organisms including plants possess a ubiquitous enzymatic pathway, the glyoxalase system, for detoxification of MG (Figure 1). The glyoxalase system consists of glyoxalase I (Gly I) and glyoxalase II (Gly II). The former catalyses the conversion of MG to S-D-lactoylglutathione in the presence of glutathione. The latter hydrolyses the resultant glutathione thiolester to D-lactic acid and glutathione. Though both the enzymes of the glyoxalase system have been extensively studied in microbial and animal systems (Rhee et al., 1987; Thornalley, 1990), very little work has been done in plants. Recently the presence of this pathway has been documented in plants and the two enzymes, Gly I and Gly II, of this pathway have been purified and characterized from different plant species. In this chapter, we will review the work on the characterization and functional significance of the glyoxalase system in plants, especially with respect to its role under abiotic stress conditions.
