Fig. 1.

Fno catalyzed ²²Na⁺ transport. Membrane vesicles (protein concentration 3.2 mg/mL) in 50 mM Mops buffer containing 20 mM MgSO₄, 20 mM NaCl, 8 mM DTE, and 2.25 mg/L resazurin translocated ²²Na⁺ upon addition of 7.5 μg ferredoxin, 5 mM titanium citrate, and 3.5 mM NAD⁺ (squares). In control experiments titanium citrate (downward-pointing triangles) or NAD⁺ (upward-pointing triangles) were omitted. Arrow indicates addition of NAD⁺.