Towards light‐mediated sensing of bacterial comfort

Bacterial comfort is central to biotechnological applications. Here, we report the characterization of different sensoring systems, the first step within a broader synthetic biology‐inspired light‐mediated strategy to determine Escherichia coli perception of environmental factors critical to bacterial performance. We did so by directly ‘asking’ bacterial cultures with light‐encoded questions corresponding to the excitation wavelength of fluorescent proteins placed under the control of environment‐sensitive promoters. We built four genetic constructions with fluorescent proteins responding to glucose, temperature, oxygen and nitrogen; and a fifth construction allowing UV‐induced expression of heterologous genes. Our engineered strains proved able to give feedback in response to key environmental factors and to express heterologous proteins upon light induction. This light‐based dialoguing strategy reported here is the first effort towards developing a human–bacteria interphase with both fundamental and applied implications.