L-Canaline: A potent antimetabolite and anti-cancer agent from leguminous plants

L-Canaline, the L-2-amino-4-(aminooxy)butyric acid structural analog of L-ornithine' is a powerful antimetabolite stored in many leguminous plants. This nonprotein amino acid reacts vigorously with the pyridoxal phosphate moiety of vitamin B-6-containing enzymes to form a covalently-bound oxime that inactivates, often irreversibly, the enzyme. Canaline is not only capable of inhibiting ornithine-dependent enzymic activity, but it also can function as a lysine antagonist. Recently, this natural product was found to possess significant antineoplastic in vitro activity against human pancreatic cancer cells.