. 2020 Apr 20;9:e53479. doi: 10.7554/eLife.53479

Table 2. Buffers used for Reconstitution and Flux Assays.

Buffer R	Buffer F	Ion flux monitored	Protein-lipid ratio (µg/mg)	Protein per assay (µg)
Comparing turnover rates at pH 7.5 and 4.5 (Figure 4)
333 mM KCl, 55 mM Na-citrate, 55 mM Na₂HPO₄, pH 6.0 pH adjustments by adjustment buffers (10x) (after reconstitution): • 0.16 M citric acid, 0.42 M Na₃PO₄ (for pH 7.5) • 0.43 M citric acid, 0.29 M Na₃PO₄ (for pH 4.5)	333 mM K-isethionate, 55 µM KCl, 55 mM Na-citrate, 55 mM Na₂HPO₄, pH 6.0 pH adjustments by adjustment buffers (10x): • 0.16 M citric acid, 0.42 M Na₃PO₄ (for pH 7.5) • 0.43 M citric acid, 0.29 M Na₃PO₄ (for pH 4.5)	Cl^–	0.4–0.8	0.4–0.8
Testing H⁺ pumping of mutants (Figure 9; Figure 9—figure supplement 1)
300 mM KCl, 40 mM Na-citrate, pH 4.0	300 mM K-isethionate, 50 µM KCl, 2 mM Na-citrate, pH 4.3	H⁺ and Cl^–	0.4–5.0	0.4–10
Testing DEER samples (Figure 7—figure supplement 1)
300 mM KCl, 40 mM Na-citrate, pH 4.5	300 mM K-isethionate, 50 µM KCl, 2 mM Na-citrate, pH 4.5	Cl^–	0.4	0.4–0.5