By Corinna Wu
Cleaning up contaminated soil, a process called bioremediation, may one day be a routine job for bacteria. Bringing that possibility closer, researchers have completed the first field study of a bacterium that not only breaks down organic chemicals that contaminate soil but also lights up to indicate that it’s working.
Scientists at the University of Tennessee in Knoxville and Oak Ridge (Tenn.) National Laboratory created a genetically engineered bacterium known as Pseudomonas fluorescens HK44. “It was engineered to produce light when it sees hydrocarbon contaminants,” says Tennessee’s Gary S. Sayler. The scientists fused a gene from a luminescent marine bacterium into the soil bacterium’s gene sequence associated with a biochemical pathway for breaking down naphthalene. When the bug feasts on naphthalene, it glows.