Photocontrol of Bacteria Bioelectric Language

The possibility to control living matter with exogenous stimuli can have tremendous impact on synthetic biology, medicine and materials science, among others. For instance achieving control over cells behaviour remains a challenge at the interface between living and non-living matter, and would enable the development of new bio-mimetic and bio-enabled materials able to perform tasks. Within this context, bacteria have arisen as “active and actively-controllable materials”, exhibiting neuro-like behaviour, extended bioelectric signalling&lt;span style="font-size:10.8333px"&gt; &lt;/span&gt;and tunable assembly properties.&lt;span style="font-size:10.8333px"&gt; &lt;/span&gt;In the last decade, it has been observed that the regulatory element of such an active behaviour is the electrical potential across the membrane, which governs bacteria electrophysiology, metabolisms and bioenergetics.&lt;span style="font-size:10.8333px"&gt; &lt;/span&gt;Light can be a powerful tool in these regards, as one can control the membrane potential and, thus, cell function and behaviour remotely and with relatively high spatiotemporal precision.<br/>Here, I will show that membrane partioning of azobenzenes in bacteria can render these organisms responsive to light, without any genetic modification. In particular, we found that the isomerization reaction at the membrane location induces either hyperpolarisation or depolarisation of the potential depending on the excited state deactivation pathways, within a bio-mimetic mechanism reproducing the initial fate of retinal. I show that bacterial opto-stimulation can trigger neuron-like bioelectric signalling and can highlight the role of previously uncharacterized ion channels in bacteria electrophysiology.&lt;span style="font-size:10.8333px"&gt; &lt;/span&gt;Finally, I also show recent results on the light-modulation of antibiotic uptake, as well as perspectives on the photocontrol of bacterial motion and assembly behavior in consortia.