Fig 4.

PBP3 partially compensates for the loss of SpoVD catalytic activity during asymmetric division. (a, b) Quantification of the cytological profiling of cells sampled from sporulation-inducing plates after 20–22 h of growth. White circles indicate data from each replicate, bars indicate average means, and error bars indicate standard deviation. More than 1,000 total cells and over 100 visibly sporulating cells were analyzed per sample. Data are from a minimum of three independent experiments. For representative micrographs, see Fig. S3. (a) Distribution of visibly sporulating cells among the indicated stages of sporulation. See Fig. 1b for the distribution of WT cells. (b) Proportion of cells that complete and progress beyond asymmetric division, i.e., all visibly sporulating cells, as a percentage of the total cells profiled. Note that the data are normalized to WT (dotted line) and that the spoVD^S311A data were derived from Fig. 1. ns, not significant. *P < 0.05, **P < 0.01, ****P < 0.0001. Statistical significance was determined using one-way ANOVA and Tukey’s test. (c) Western blot showing the levels of SpoVD, PBP3, and Spo0A in cells sampled from sporulation-inducing plates after ~14 h of growth. SpoVD and PBP3 are not detected in the ∆spo0A strain, which cannot initiate sporulation. *Indicates a non-specific band detected by the anti-PBP3 antibody.