Fig. 4

Electron microscopy and cryo-electron tomography (CET) of mamK D161A connected cells. ai TEM micrograph of four connected cells. Arrowheads indicate cell division sites. Scale bar: 1 μm. aii Closer view of a cell division site. Scale bar: 500 nm. b CET sections of a selected cell division site of three connected cells (n = 30). Additional file 11: Figure S8A shows a CET micrograph corresponding to the three connected cells indicating the division site imaged in “b”. Black arrowheads denote MamK filaments. Blue arrows indicate inner (IM) and outer (OM) membranes. c, d CET reconstruction of the selected cell division site in “b”. Magnetite crystals (red) enclosed by vesicles (yellow) and flanked by the MamK filament (green). The cellular envelope inner and outer membranes are depicted in blue. Flagella are represented in gold