Heavy metal pollution resulting from mining, smeltering and military activities is widespread and poses a threat to drinking water resources, food chain safety and air quality. The clean-up of metal-polluted soils is thus of great interest economically as well as for the protection of human and environmental health. Scientists at the Max Planck Institute of Molecular Plant Physiology in Potsdam and at the Leibniz Institute of Plant Biochemistry in Halle have now made pioneering progress in the understanding of the molecular mechanisms that enable some plant species to accumulate metals specifically in their leaves while thriving on metal-polluted soils (The Plant Journal, OnlineEarly, 4-Dec-2003). The scientists were the first to accomplish a global comparison of gene activity in the zinc and cadmium hyperaccumulator species Arabidopsis halleri and the genetic model plant Arabidopsis thaliana, thereby identifying key metal homeostasis proteins. These could serve as a basis for the development of new plant-based and cost-effective technologies for cleanup or stabilization of metal-contaminated soils.

In the 1980s scientists began laboratory studies on metal hyperaccumulator plants, i.e. plants which accumulate exceptionally high concentrations of heavy metals in their above-ground biomass. This coincided with the recognition that a number of serious human diseases are the result of disruptions in metal homeostasis, for example Menke's disease, Wilson's disease, hemochromatosis and possibly Alzheimer and prion diseases. Indeed, metal ions are essential all across the kingdoms of life, buttheir role in biology is ambiguous: small amounts of metals like iron, manganese, zinc, copper and nickel are essential. However, serious damage occurs when any heavy metal is accumulated in excess or distributed incorrectly within an organism. Therefo
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Contact: Dr. Ute Krmer
kraemer@mpimp-golm.mpg.de
49-331-567-8357
Max-Planck-Gesellschaft
4-Dec-2003