BACTERIAL cells have been fitted with an artificial system that makes gene expression dependent on an external signal.
James Liao’s team in the University of California at Los Angeles added the gene for green fluorescent protein to E. coli, but linked its expression to the level of acetate in the growth medium (Proceedings of the National Academy of Sciences, DOI: 10.1073/pnas.0306484101). Acetate is produced naturally by the bugs, and when its concentration passed a certain threshold the bacterial colony suddenly lit up.
The work, which mimics natural processes, could lead to ways of improving the efficiency of processes used…
