TABLE 2.
Dilution buffers used for artificial imposition of (electro-)chemical ion gradients in proteoliposomes
| Buffera | Forces | Composition of buffer | pH |
|---|---|---|---|
| 1 | No gradient | 10 mm Tris-Cl, 10 mm potassium Pi, 100 mm Na2SO4, 100 mm NH4SCN | 6.8 |
| 2 | SMF plus PMF | 10 mm Tris-Cl, 10 mm potassium Pi | 7.5 |
| 3 | SMF | 10 mm Tris-Cl, 10 mm potassium Pi, 50 mm (NH4)2SO4 | 6.8 |
| 4 | PMF | 10 mm Tris-Cl, 10 mm potassium Pi, 100 mm Na2SO4 | 7.5 |
| 5 | ΔpNa | 10 mm Tris-Cl, 10 mm potassium Pi, 100 mm NH4SCN | 6.8 |
| 6 | Δψ | 10 mm Tris-Cl, 10 mm potassium Pi, 100 mm Na2SO4, 50 mm (NH4)2SO4 | 6.8 |
| 7 | ΔpH | 10 mm Tris-Cl, 10 mm potassium Pi, 100 mm Na2SO4, 100 mm NH4SCN | 7.5 |
a Proteoliposomes were prepared in Buffer 1 and diluted 100-fold in Buffers 1–7 with composition and pH as indicated in the third and fourth columns, respectively, to achieve no gradient, SMF interior positive and high) and/or PMF interior positive and acidic) or their components as indicated in the second column.