Figure 1.

Schematic representation of a molecular system for the uptake and degradation of small organic molecules. A light-driven proton pump (red) is activated by light (h^.v) generating a proton gradient (indicated by different sizes of [H⁺]) across a vesicular structure (e.g., liposome, in orange). A proton-driven transporter (in blue) accumulates the target substrate (S), e.g., a $\mathrm{\beta }$-lactam antibiotic, inside the vesicle using the established proton gradient. Enzymes (in brown) entrapped inside the vesicle degrade the substrate to a non-active compound (P). Depicted modules are based on structures of proteorhodopsin (in red, PDB ID code: 2L6X), YePEPT (in blue, PDB ID code: 4W6V) and TEM1 β-lactamase (in brown, PDB ID code: 1BTL).