1. Time-lapse microscopy of a growing single cell with fluorescently labeled cell wall.
Time-lapse microscopy of a growing single cell with fluorescently labeled cell wall. (A to C) Phase-contrast and fluorescent images (upper and lower rows, respectively) of a ΔminC E. coli cell on an agar pad at 90-min intervals. The wall of the cell was initially pulse-labeled with Alexa Fluor 488. Because, after the pulse-label, new cell wall synthesized during growth is not fluorescent, the label serves as a marker for the original cell wall. From the first to the last image, the cell elongates from approximately 2.5 to 4 μm over 180 min, an 80% increase in length. Note that while the middle cylinder of the Alexa image at 180 min (C) is darker, the pole and minicell are brighter. Thus, new growth appears to be concentrated in the middle cylinder of the cell and the minicell receives the older cell wall.
Camilla U. Rang et al. mSphere 2018; doi: /mSphere