Fig. 7. Real-time metal transport in CmΔZntA proteoliposomes monitored with fluorescent probes encapsulated in the proteoliposome lumen. (a) Leadmium Green (20 μM) reporting Pb²⁺ transport (λ_exc = 490 nm; λ_em = 520 nm), (b) Fluozin-3 (10 μM) reporting Zn²⁺ transport (λ_exc = 480 nm; λ_em = 515 nm), (c) Fluozin-3 (10 μM) reporting Cd²⁺ transport (λ_exc = 480 nm; λ_em = 515 nm), and (d) Calcium Green (10 μM) reporting Hg²⁺ transport (λ_exc = 506 nm; λ_em = 531 nm). Red lines correspond to M²⁺ transport traces with standard deviations shaded in red. Black – proteoliposomes supplemented with M²⁺ and ATP but no Mg²⁺. Blue – proteoliposomes supplemented with M²⁺ and Mg²⁺ but no ATP. Signals were normalized for the relative turn-on fluorescence response of different probes, and corrected for background signals of control liposomes. All data are mean ± s.d. (n = 3).