Induction of Phytochelatin. (Class III Metal loth ionein) and Incorporation of Copper in Transformed Hairy Roots of Rubia tinctorum Exposed to Cadmium

Abstract

Summary Hairy roots of Rubia tinctorum L. were cultured in Murashige-Skoog liquid medium containing cadmium. (Cd) chloride. (100 µmol/L), and the induction of phytochelatin including desglycyl type. (PC) was studied using a high performance liquid chromatograph connected with an inductively coupled plasmaatomic emission spectrometer. The total Cd concentration in the hairy roots was kept almost constant from days 1 to 14 during Cd exposure, but the portion that was recovered from the supernatant fraction increased with time. The increase reflected the induction of Cd-binding PC. The PC also contained copper as a metal constituent. When the metal composition in PC induced by Cd was compared in the hairy roots and the normal root cultures of R. tinctorum , the latter showed a notably higher Cu/Cd ratio, mainly due to a lower Cd level.