Accumulation of Cadmium by Transgenic Tobacco Plants (Nicotiana tabacum L.) Carrying Yeast Metallothionein Gene Revealed by Electrochemistry

摘要

Phytoremediation of heavy metals includes phytoextraction and phytoaccumulation, i.e. accumulationof pollution from soils or water into the plants. Inorganic pollutants like heavy metals cannot bechemically degraded and thus it has to be accumulated in roots and leaves of the plants in non-toxicforms. In this study, the influence of cadmium on transgenic Nicotiana tabacum plants carrying yeastmetallothionein was investigated. Tobacco plants were exposed to 0, 50, 100 and 250 M CdCl2 for 96hours. Growth parameters as well as changes in content of cysteine, oxidized/reduced glutathione,phytochelatins (PC2, PC3 and PC4) were monitored using high performance liquid chromatographywith electrochemical detection. Moreover, we exploited differential pulse voltammetry Brdickareaction for determination of metallothionein and verified the results obtained by dot blot assay. Inaddition, all results were compared with results obtained using non-transgenic tobacco plants. Ourresults indicate protective role of metallothionein as well as its role in cadmium accumulation in rootsof transgenic plants.