Phytochelatin biosynthesis and function in heavy-metal detoxification

Plants respond to heavy-metal toxicity via a number of mechanisms. One such mechanism involves the chelation of heavy metals by a family of peptide ligands, the phytochelatins. Molecular genetic approaches have resulted in important advances in our understanding of phytochelatin biosynthesis. In particular, genes encoding the enzyme phytochelatin synthase have been isolated from plant and yeast species. Unexpectedly, genes with similar sequences to those encoding phytochelatin synthase have been identified in some animal species.