Figure 4. Correlative SEM reveals cell-cycle dependent early signs of mechanical fracture.

(A–D) Representative correlative fluorescence (top) and SEM images (bottom) of S. aureus Newman cells stained with FM 4-64, showing the cell surface features at different stages of the cell cycle. 98% (n=54) of the cells with visible holes (blind analysis, see Methods) had completed septa, while only 49% (n=108) of the cells with completed septa had holes.