A non-natural Nicotinamide cofactor for biotransformation at extreme conditions
September 15-19, 2019
Redox enzymes are very useful tools for establishing greener routes in organic synthesis, mostly due to their highly selective reduction, oxidation and oxyfunctionalisation reactions. However, the metastable nicotinamide cofactors (NAD/P(H)), required for catalysis, are prone to fast degradation, when utilized under non physiological conditions. Establishing of robust artificial enzymatic cascade reactions and cell free biotransformations at extreme conditions is therefore still a major challenge. We show one NAD(P)+ derivative with highly increased stability and very similar redox potential compared to its natural counterpart that can be used very efficiently with a number of biocatalysts. We have tested more than 50 redox enzymes and found a substantial number of them being able to utilize the nicotinamide derivative. Among them, we also successfully identified those that are commonly used in cofactor regeneration systems. Applying enzyme engineering to a model enzyme, it was possible to develop variants with activities even higher than towards the natural cofactor, allowing efficient biotransformations at 60°C and above for many hours.
In addition further characterization and additional comparative molecular dynamic simulations revealed an improved understanding of the biomimick’s recognition on a molecular level, facilitating the transfer to other enzymes.
Volker Sieber, "A non-natural Nicotinamide cofactor for biotransformation at extreme conditions" in "Enzyme Engineering XXV", Huimin Zhao, University of Illinois at Urbana-Champaign, USA John Wong, Pfizer, USA Eds, ECI Symposium Series, (2019). https://dc.engconfintl.org/enzyme_xxv/19