Extended Data Figure 2. S. aureus live cell architecture.

a, At the interface between the most recent division plane and the mature cell wall we find a sharp topographic step between the mature (mesh) and recently synthesised cell wall (concentric rings), see black arrows. DS = 535 nm, 3D details: Z aspect ratio = 1, Pitch = 21°, Light rotation = 103°, Light Pitch = 49°, Light Intensity = 70%, Plot type = mixed. b, Same image as a but processed with a Plane Fit at 3^rd order showing the sharp interface in more detail. DS= 27 nm. c, profile from taken along the dotted black line in a, showing a sharp change in height at the interface between the mesh and the rings (see red arrow corresponding to red arrow head in a). d-g are a series of images, each from a different cell, showing the presumed time evolution of the ring architecture. Samples naturally contained cells with a distribution of times since their last division, and hence showing differing levels of maturation of the peptidoglycan at the extracellular surface of the most recent division plane. d, Recently revealed outer septal surface showing dense concentric rings. The blue dashed box shows the location of Fig 1e in the main text. DS = 18 nm. e, Image of a different cell showing what is probably the next stage of maturation. The rings are still prominent (white arrows), but show larger spacing, greater height variation and pores have appeared in the surface. Features oriented approximately along the radial direction are also apparent. DS = 23 nm. f, A different cell showing the subsequent stage where, underneath the rings, the pores of the mesh have started to appear. DS = 38 nm. g, The last stage of maturation of the cell wall is the completely disordered mesh without any traces of former ring structures. DS = 30 nm. The morphologies from a-b were also detected in at least 1 other biological independent repeat (see repository) and from d-g were also detected each in at least 2 other biological independent repeats (see repository).