Figure 4. Hydride flow.

An illustration of two experimental approaches to examine the hydride flow in the reaction catalyzed by the thermophilic tmFDTS at reduced temperature (37 °C). Experiment A was performed in a D₂O buffer using 6H-dUMP (i.e., unlabeled, dUMP). Experiment B was performed in an H₂O buffer using 6D-dUMP (see SI). Percentages below each species represent the relative quantities of product formation as indicated by ¹H and ²H NMR.