PHYTOCHELATINS (CLASS-III METALLOTHIONEINS) AND THEIR DESGLYCYL PEPTIDES INDUCED BY CADMIUM IN NORMAL ROOT CULTURES OF RUBIA-TINCTORUM L

Normal root cultures of Rubia tinctorum L, were exposed to cadmium (Cd ) with or without glutathione (GSH). The Cd-binding substances thus in duced were detected by high performance liquid chromatography (HPLC) w ith an inductively coupled plasma-atomic emission spectrometer as the metal detector and by postcolumn derivatization HPLC based on the dete ction of metal and thiol group, respectively. The substances were frac tionated and identified as phytochelatins (PCs), (gamma-Glu-Cys)(n)-Gl y (n = 2-5), and their desglycyl peptides, (gamma-Glu-Cys)(n) (n = 2-4 ). GSH in the culture medium increased the amount of induced PCs and t heir desglycyl peptides.