GM Tobacco in Cleaning TNT Contaminated Soil

A group of researchers from Oxford, Glasgow and Cambridge developed GM tobacco plants capable of cleaning trinitrotoluene (TNT) contaminated soil. TNT is one of the most widely used explosive, and its toxic, mutagenic and highly energetic properties threaten human health as well as the environment. TNT contamination is still a major problem in many World War II sites, sites of explosive manufacture and military training grounds. Although several soil bacteria with the ability to metabolize TNT have been isolated, their activity is insufficient to degrade TNT at any appreciable rates.

Author Neil Bruce and colleagues inserted two genes from the bacteria, Enterobacter cloacae, encoding TNT-transforming enzymes (nitroreductase) into a tobacco plant. They compared the effects of the transgenic tobacco on TNT contaminated soil with that of the wild type plant. Results showed that GM tobacco significantly reduces the toxicity of TNT contaminated soil. The transgenic plants also showed increase TNT tolerance as compared to the wild type. In addition, they proved to be beneficial for the microbial flora, as they increased the functional and genetic diversity of the bacterial community in acutely polluted soil. In uncontaminated soil, nitroreductase expression did not show any effects in the natural microflora and surrounding plants. Their findings might have important applications, not only for the use of genetically engineered plants for TNT remediation, but also for cleaning up other sources of contamination.

The complete article is scheduled for release at the Aug 15 issue of the American Chemical Society’s Environmental Science and Technology http://pubs.acs.org/cgi-bin/sample.cgi/esthag/asap/pdf/es070507a.pdf or read the ACS’ new release at http://acswebapplications.acs.org/applications/ccs/application/index.cfm