Preliminary results on cadmium and mercury tolerance mechanisms in Nicotiana sp.

The response to cadmium and mercury have been investigated in Nicotiana sp. cell suspension cultures. In cadmium-treated cells the presence of cadmium-induced peptides were seen. These peptides with an apparent molecular weight of approximately 10 000 Da are probably constituted by phytochelatines (PCs), gluthatione derivative peptides, that generally have an important role in the cadmium tolerance mechanisms of most higher plants. On the contrary the presence of mercury-induced peptides is yet less clear due to analytical problems. The improvement of the analytical methodology will be the next step in our research.