Purple Poop? Pigment Producing E.coli As BioSensors
What do you get when one artist, one designer and seven Cambridge University biology undergraduates engineer a new strain of E.coli? Purple poop.
Actually, colored poop is just one of a rainbow of potential applications for E. chromi, an engineered strain of E. coli that secretes color in the presence of pollutants. E. coli bacteria are sensitive to environmental pollutants. When the team of artists and scientists equipped them with a pigment-producing device that switches on in the presence of various toxins, they created a way to use bacteria as an inexpensive, user-friendly biosensor.
Potential applications include a cheap disposable biosensor for arsenic and probiotic drink that would alert patients to possible ailments by coloring their poop. A purple output, for example, may indicate the presence of a Salmonella infection.
E. chromi won MIT’s International Genetically Engineered Machine Competition in 2009, was a finalist for the 2011 Index Awards, and a winner of the 2011 World Technology Awards. Although it may sound unusual, this isn’t the only example of a bacterial biosensor. Scientists at the University of California San Diego (UCSD) recently attached a fluorescent protein to some E.coliand synchronized the colony to flash on and off like a neon sign. When the blinking colony detected low levels of arsenic, it slowed its rate of flashing.
