Figure 4.

Representative POR photolysis transients measuring hydride transfer (upper, left), deuteride transfer (upper, right), proton transfer (lower, left) and deuteron transfer (lower, right) at 1 bar (black), 1 kbar (red) and 2 kbar (blue). Transients are fitted to a single exponential function (solid line), with averaged rate constants given in Table 1. Conditions: 50–260 μm POR (Table 1), 10 μm Pchlide, 500 μm NADPH, 0.1% 2‐mercaptoethanol, 0.1% Triton, 50 mm Tris, 150 mm NaCl, pH 7.5, 298 K. Deuteride transfer was measured using (S) ‐ [4‐²H]‐NADPH and deuteron transfer was measured in D₂O buffer, pD 7.5.