Fig. (3).
An illustration of the competitive pathways of drug uptake and efflux traversing the lipopolysaccharide bilayer and the outer and inner cell membranes of Gram-negative pathogens. The active extrusion of drug molecules occurs via single and multi-component efflux pumps, where the multi-component tripartite complex comprises a membrane fusion protein, an efflux protein pump in the inner membrane and an outer membrane protein.