Fig. 2: Cryo-ET studies of minicells with and without pepD2M treatment.

a A representative square of a Quantifoil R 2/2 Holey carbon grid loaded with minicells. b A zoomed-in image of the red box in (a). Minicells could be in a hole or on the carbon film. c Two untreated minicells with an enlarged periplasm. d A tomographic slice of an untreated minicell. e A zoomed-in image of the blue box in (d). OM: outer membrane; PG: peptidoglycan; IM: inner membrane. f The average distance between the OM and PG is 10.7 ± 0.1 nm (mean ± standard deviation). Eleven minicells were measured. Each minicell was measured twice at different locations. The plot is presented as 25th percentile, median, and 75th percentile, with Tukey whiskers representing ±1.5 × the interquartile range. g–l Tomographic slices of minicells treated with pepD2M to show examples of five morphological changes. g Change 1: pore formation (yellow arrow). h Change 2: shrunken cell (red arrow). i Chang 3: low-density membrane (blue arrow). j–l Change 4: lipid cluster (black arrowhead); Change 5: lipid cluster with cell residuals inside (white arrow). The scale bar represents 100 nm. The insets in g and h are the enlarged image from the box. IM: cyan; OM: violet. m Counts of changes 1‒5 after the treatment with different concentrations of pepD2M. n The proportion of Changes 1‒5 occurrence in 123 tomograms.