Detection of landmines with bacterial biosensors

Abstract natural soil bacteria can alter their metabolism so that explosive related compounds in the soil can be used to provide energy for their life activities. When an organic compound (in this case DNT) from the environment appears inside of the bacterial cell it binds to a regulator protein (DntR), which causes a change in the protein shape and activates the regulator protein. Upon activation it binds to a specific location on the DNA matrix, which initiates the reading process and results in synthesis of the appropriate enzyme that can digest the organic compound. In this project the DNA-matrix coding for the digestive enzyme has been removed and a gene coding the green fluorescence protein (GFP) has been inserted. Upon exposure to DNT the modified bacteria synthesis GFP, this results in emission of visible light upon UV-illumination. The structure of DntR has been determined and the organic compound (DNT) can fit into a specific cavity. The sensitivity in the binding cavity has to be modified so that DNT binds stronger and other compounds bind weaker. For this work modeling is performed with different compounds in the cavity to determine which amino acids should be changed.