Fig. 5.

Steady-state kinetic analysis of the oxidation of manoyl oxide by CYP76AH24. The enzymatic activity of CYP76AH24 was evaluated using varying concentration (1–75 μM) of manoyl oxide substrate and 80 pmol of enzyme. The produced 11β-hydroxy-manoyl oxide was quantified by CG–MS analysis using purified compound as standard. Quantification of CYP76AH24 enzyme concentration was performed by measuring the binding of CO to the reduced form of the purified enzyme (450 nm peak), according to [47]. The differential spectrum of the CO-treated enzyme preparation is shown in the inset