Bioluminescent Whole-Cell Optical Fiber Sensors

In order to assess the potential hazards inherent in contaminated soils and aquifers, it is essential that their toxicity, including genotoxicity, be properly evaluated. While several methodologies exist for rapid testing of acute toxicity, there is a lack of “user friendly” bioassays for genotoxicity (mutagenicity, etc.) monitoring. A novel approach has recently been proposed, in which genetically engineered bacteria are used as test organisms. In these bacteria, bioluminescence (lux) genes are fused to promoters of genes that are involved in the defense against various types of stress (i.e., DNA damage, heat shock or protein damage, heavy metal and oxidative stress). In the presence of damaging agents, therefore, when these genes are induced, the bacteria emit light in a dose-dependent manner. This application has been adapted to field measurements by immobilizing these reporter cells on optical fibers in order to create self-contained optrode sensors.