Biotech Updates

GM Tobacco to Clean-up Soil and Groundwater Contaminant

July 11, 2008

Plants are increasingly being employed to clean-up environmental pollutants like heavy metal. They can act as solar-powered pump-and-treat systems, capable of extracting these contaminants from polluted soils and metabolize or store them afterwards in specialized tissues. However, a major limitation of phytoremediation is the inability of plants to mineralize most organic pollutants.

Scientists from the University of York and University of Edinburgh in the United Kingdom developed transgenic tobacco that can accumulate and ‘detoxify’ the haloalkane 1,2-dichloroethane (1,2- DCA). 1,2 DCA is used in the synthesis of vinyl chloride. The U.S. Environmental Protection Agency has listed the compound as a priority pollutant and probable human carcinogen.

The scientists inserted the bacterial genes dhlA and dhlB genes into the tobacco genome. The genes encode enzymes, typically lacking in plants, that have the ability to detoxify a range of halogenated aliphatics (such as 1,2-DCA). The authors pointed out that their findings represent a significant advance in the development of a low-cost, phytoremedial approach toward the clean-up of halogenated organic pollutants from contaminated soil and groundwater.

The paper published by the journal Plant Physiology is available to subscribers at http://www.plantphysiol.org/cgi/content/full/147/3/1192 Non subscribers can read the abstract http://www.plantphysiol.org/cgi/content/abstract/147/3/1192