Engineering a bacteriophytochrome switch – creating a controllable E. coli chameleon

Photoreceptors are utilized by almost every organism to adapt to their ambient light environment. Our aim is to engineer a novel reversible molecular 'light switch' within E. coli by introducing a photoreceptor from non-photosynthetic bacteria (D. radiodurans and A. tumefaciens). By cloning the bacteriophytochrome coupled with heme-oxygenase, an enzyme that produces biliverdin from heme, the created colonies are able to respond to red and far-red light environments. This novel approach results in the colour of the E. coli 'switching' from blue to green. Our E. coli chameleon will serve as a fundamental 'bio-brick' for future applications by providing a simple and photo-reversible switch.