Researchers at UC San Diego have built a bacterial light source of about 13,000 "biopixels," as they call it. Their work on synchronized fluorescent protein expression was published in Nature last week. This is not only a new form of art but also a piece of high-tech bioengineering. The light-producing chips consist of more than 50 million bacteria that interact and synchronize with each other using a mechanism known as quorum sensing, a method in which bacteria communicate with their fellows and gives them group-like behavior. They can regulate gene expression according to the density of the population or to determine adaptation strategies to their local environment.

The researchers in San Diego coupled the expression of a fluorescent protein to a biological clock which is synchronized with other colonies using a quorum-sensing mechanism. In this way the bacteria will periodically fluoresce in unison like blinking light bulbs.

Besides being a biological psychedelic groove light, this technique can be used for useful applications. For example, researchers can create the group-engineered bacterial sensor capable of detecting low levels of arsenic in which decreases in the frequency of the oscillations of the cells' blinking pattern indicate the presence and correlate with the amount of the arsenic poison. They foresee that this approach can be used to detect heavy metal pollutants and disease-causing organisms in a low cost array.