Fig. 5.

Hydride and proton transfer transients of wild-type and Thr230 variant POR enzymes. Typical laser transients showing the absorbance change at 696 nm for the wild-type POR and the Thr230 variants. The formation of the absorbance band at 696 nm represents hydride transfer and the disappearance of the 696 nm band represents proton transfer [15]. The transients were measured using an equal ternary complex concentration based on the Pchlide binding constant for each enzyme. The experimental procedure is described in the materials and method section.