Monday, July 25, 2011: 9:00 AM
Nottoway, 4th fl (Sheraton New Orleans)
The contamination of the environment with toxic explosives presents a serious and widespread problem at sites across the world. Our recent studies on the biodegradation of energetic compounds have resulted in the isolation of bacteria from explosive-contaminated land that are capable of metabolizing TNT and RDX. These studies have identified a number of interesting enzymes including a unique cytochrome P450 XplA from a strain of Rhodococcus rhodochrous that degrades RDX. Our work has also been targeted on the use of genetic engineering for broadening and improving the degradative capabilities of plants for phytoremediation of explosives pollution. Significant progress has been made towards this goal and we have successfully combined the biodegradative capabilities of soil bacteria with the high biomass and stability inherent to plants. These transgenic plants can efficiently remove toxic levels of TNT and RDX from contaminated soil and water. Plants have had to evolve complex mechanisms to tackle a diverse range of toxic compounds that they might encounter. In an effort to determine how plant tolerance could be further improved, we have been investigating the enzymology underlying the innate ability of plants to detoxify TNT. In addition, we have been engineering rhizosphere bacteria to further enhance the ability of plant systems to degrade RDX.
As a result of recent advances in our knowledge of the biodegradation of explosives, endogenous plant detoxification systems and the use of genetic engineering, our work on transgenic plants is now poised for testing in the field.