Fig. 2.

High-resolution AFM imaging of OMVs collected from E. coli overexpressing Omps. a Overview AFM topograph of an OMV enriched in Tsx adsorbed to mica. Upon adsorption to mica the OMVs opened as single layered membrane patches. For topographs of other OMV types see Supplementary Fig. 4. b Intermediate resolution topograph of the surface of the OMV shown in (a). Unstructured areas (lighter) alternate with homogeneously structured areas (darker). Both areas contain sparsely distributed particles protruding higher from the membrane. c High-resolution topograph of a lower protruding area reveals Omps (single protrusions) in densely packed arrangements. AFM topographs were recorded using contact-mode AFM in buffer solution (DPBSS) at room temperature (see Methods). The full color ranges of the topographs correspond to vertical scales of a 16 nm, b 4 nm and c 1 nm. Scale bars, 200 nm (a), 50 nm (b) and 20 nm (c)