Journal: eLife
Article Title: Two different cell-cycle processes determine the timing of cell division in Escherichia coli
doi: 10.7554/eLife.67495
Figure Lengend Snippet: ( A ) Top: Snapshots of a single mother-machine channel. Interval between images is 12 min. Red: cytoplasmic mCherry, yellow: YPet-DnaN. The contours show a cell growing for two consecutive cell cycles. Bottom: Cell length (gray line), the position of YPet-DnaN foci along the long axis of the cell (black dots), initiation and termination times (red and yellow dashed lines, respectively) in the same cells shown in A. Scale bar: 2 μm. ( B ) Top: Snapshots of E. coli S233 (NCM3722, λ ::P-mcherry, dnaN::Ypet-dnaN ) treated with sublethal amounts of A22 (concentrations in μg.mL -1 ). Scale bar: 2 μm. Bottom: Effect of A22 treatment on average dimensions of cells grown in liquid or in mother machine for at least 6 hr of exponential growth. For cell-to-cell variations see Figure ( C ) Duration of inter-division time, I, C, and D periods as a function of average cell width measured in mother machines. Blue and gray squares represent unperturbed conditions and A22-treatment, respectively. Each symbol represents an independent biological replicate. ( D ) Conditional probability density of the occurrence of YPet-DnaN foci p ( y | t ) as a function of cell length (y-axis) for different time points before subsequent cell division (x-axis) for different A22 concentrations as indicated on top of the maps. Maps are duplicated for better visualization of the replication process. Vertical lines indicate the beginning and end of the probability peaks that correspond to replication initiation and termination, respectively. Note that these times do not strictly agree with average replication/termination times. Figure 2—source data 1. Data used to generate and its supplements.
Article Snippet: To that end we identified fluorescent spots of Ypet-DnaN: First, a bandpass filter was applied to the YPet fluorescence image (Matlab function bpass with 0.8 px and 20 px for the characteristic length scales of noise and objects, respectively).
Techniques: