Unique kinetic behavior of a secondary alcohol dehydrogenase: from a reaction engineering point of view

This study investigates the atypical kinetics of an (S)-selective oxidoreductase during the oxidation of (S)-rhododendrol to raspberry ketone. The enzyme kinetics exhibit a biphasic pattern: one follows classic Michaelis-Menten kinetics, while the other shows substrate inhibition, which is consistent with the presence of two distinct substrate interaction modes. One site is highly susceptible to product inhibition, whereas the other is less affected. In contrast, only a single binding site is evident for the coenzyme. By applying bioreaction engineering principles, we gained a deeper understanding of the reaction mechanism, highlighting the importance of this approach in studying enzyme-catalyzed reactions. Based on kinetic examinations and operational stability of the enzyme, a mathematical model was developed and validated in a batch reactor. This study provides a valuable basis to future interdisciplinary research in areas such as enzyme engineering and mechanism studies, drug design, and bioprocess development, enabling the full exploitation of its potential in industrial and biomedical applications.