Copper (II) complex with L-carnosine as a ligand: the tautomeric change of the imidazole moiety upon complexation

Carnosine (?-alanyl-L-histidine) is found in skeletal muscles and in some other tissues of vertebrates [lj.Although its biochemical function is so far unknown, certain lines of evidence support its important role in the biochemistry of copper. In fact, it has been suggested that by chelation of copper ions, carnosine may act as antioxidant in vivo and be involved in regulation of anaerobic glycolisis of skeletal muscle [2]. In addition, this dipeptide is a substrate for the metal-activated enzyme carnosinase. Consequently, a better knowledge of the interaction of copper ions with carnosine can be helpful in rnetalenzyme studies and in understanding the biological role of this dipeptide.