Light regulation of c-di-GMP-dependent motility and biofilm phenotypes in E. coli. a, Setup of the red and blue light panels. b, Inhibition of swimming in the semi-solid agar in strain MG1655[DE3] expressing the red light-activated DGC, BphS (plasmid pETBphSO). c, Restoration of swimming in the semi-solid agar in strain MG1655 ΔyhjH expressing the blue light-activated PDE, MBP-EB1 (plasmid pMal-EB1). d, Induction of curli fimbria formation in BL21[DE3] expressing the red light-activated DGC, BphS, (plasmid pETBphSO).