Figure 5. Stopped flow analysis of the influence of divalent cations on NH₃ fluxes.

The effect of Hg⁺⁺ and Cu⁺⁺ on individual time courses of fluorescence change were analysed in RhCG-proteoliposomes after incubation with 0.1 mM HgCl₂ (A) or 0.21 mM CuSO₄ (B). For reversion, the β-mercaptoethanol (βme at 5 mM) and the Gly-Gly-His peptide (GGH at 2 mM) were used. Results (means of several independent experiments +/− SEM) regarding the effect of divalent cations (A:+Hg⁺⁺ and B:+Cu⁺⁺) and reversions (A: +βme and B:+GGH) on transport activities (corresponding to alkalinisation rate constants after removal of the constant value of empty liposomes) are reported in inserts. The number of experiments is mentioned above each bar.