Figure 13.

Directed evolution of an amine oxidase.¹²³ (A) Coupled assay used to screen for amine oxidase activity. The amine substrate is oxidized, yielding H₂O₂ as byproduct, which oxidizes Amplex UltraRed to Resorufin. (B) After one round of directed evolution, the active site of the enzyme is remodeled by introduction of five mutations. (C) The variant yielded from directed evolution (PT.1, blue) has a 960-fold improved k_cat/K_M. We thank Prof. Donald Hilvert for providing the material for the subfigures B and C.