Figure 2.

Examples of topologies of OM lipoproteins in E. coli. OM lipoproteins (green) were assumed to adopt a typical topology with the protein domain in the periplasm and lipid anchored in the inner leaflet of the OM. By contrast, the topology of experimentally studied lipoproteins is often more complex. Lipoproteins can be assembled in interlocked complexes with beta-barrel proteins (blue) like RcsF/OMP and LptE/LptD, or they can form transmembrane multimeric channels like CsgG and Wza. Assembly of the lipoproteins at the OM often results in surface exposure of parts of the protein (RcsF, CsgG and Wza). In the case of RcsF, the lipid moiety anchors the protein in the outer leaflet of OM. (Online version in colour.)