Hebrew University of Jerusalem scientists have discovered that buried explosives leak vapors that cause engineered e-coli bacteria to emit fluorescent molecules.  Remote laser scanners detect the glowing molecules, giving explosives experts the exact locations of the deadly devices.

http://www.smithsonianmag.com/innovation/how-glowing-soil-can-help-find-land-mines-180962918/

https://www.nature.com/nbt/journal/v35/n4/full/nbt.3791.html