Depriving one bacterium of blue light drops its reproductive rate by 90%.
Dr. Bang discovered this bacterium, Brucella abortus, in 1897. (Present in unpasteurized milk, it can cause pregnant cattle to abort and causes undulant fever in humans.)
According to Science (http://bit.ly/1RIZIox ):
Brucella contains a class of signaling proteins called LOVs. In plants, these proteins react to the presence of light, oxygen, or the voltage of a weak electrical current. When activated, LOVs encourage plants to grow toward light, but their role in Brucella was unclear. When exposed to the blue wavelengths of sunlight, the LOVs in Brucella signal other proteins that tell the bacterium to reproduce at will.
I wonder if an LOV could be attached to chemotherapy, sent to tumors, and then activated safely with light, oxygen or electricity.
(And, of course, this is another reminder of why people should only drink pasteurized milk.)