Globins in Photobiomodulation of Tumor Microbiome Biofilms

The photobiomodulation of Escherichia coli bacteria under the exposure to continuous or pulsed red laser radiation with a pulse repetition rate of 2 Hz was studied. It was found that irradiation leads to an increase in the number of individual colonies, more than twofold in case of pulsed radiation, inter alia, due to the degradation of bacterial aggregates, i.e., the initiation points of biofilm formation, without affecting the light scattering parameters of the culture. A laser-inducible signaling network conjugated with globin O2 sensors, DgcO diguanosine monophosphate cyclase and PdeO phosphodiesterase, was constructed. It is supposed that the conformational shift induced by laser-induced local superheating of the chromophore is able to substitute oxygen in the control of globin O2 sensors, turning off DgcO and turning on PdeO, shifting the equilibrium towards the reduction of cyclic dimeric guanosine monophosphate, bacterial aggregates and microbial biofilms, i.e., the targets for photobiomodulation in antitumor therapy.