4.4 Confocal microscopy
All images shown in this paper were captured by Nikon A1 LFOVT. To assay compartment formation (Figures 2C and 2D) and light responses (Figures 3B, 3C and 3E) for a long period of time, we used an LB agar pad to fix 1-5 μL overnight E. coli under a microscope. The solid pad layer was made from 400 μL 1% LB agarose, on a glass coverslip-bottomed (20 mm in diameter) 35 mm Petri dish (D35-20-1-N). To observe bacterial morphology and compartment localization pattern (Supplementary Figure 2-4), recruitment of enzymes into compartments (not shown), and other short period observation, we used glass slides to fix them. All images captured were under a 100X oil immersed lens. 488 nm laser was used both for the observation of phase module distribution and the inducing light signal to trigger POI recruitment. 561 nm laser was used for the observation of POI recruitment. ProLong Live Antifade Reagent (P36975, Invitrogen) was used to avoid photo-bleaching of mCherry (1:50 dilution). Intense light induction was performed using region of interest (ROI) to guide 488 nm lasers, 3% lasted for 8 seconds (Figures 3B and 3E), while weak light induction was conducted under 2% laser intensity for 6 seconds. FRAP assays were carried out using slightly higher laser power with ROI as a single pixel.