Investigation of a Novel Type I Baeyer-Villiger Monooxygenase from Amycolatopsis thermoflava Revealed High Thermodynamic- but Limited Kinetic Stability.

Investigation of a Novel Type I Baeyer-Villiger Monooxygenase from Amycolatopsis thermoflava Revealed High Thermodynamic- but Limited Kinetic Stability. Chembiochem. 2019 Oct 14;: Authors: Mansouri HR, Mihovilovic MD, Rudroff F Abstract Baeyer-Villiger monooxygenases (BVMOs) are remarkable biocatalysts but due to their low stability, their application in industry is hampered. Thus, there is a high demand to expand the diversity and increase the stability of this class of enzyme. Starting from a known thermostable BVMO sequence from Thermocrispum municipale (TmCHMO), we identified a novel BVMO from Amycolaptosis thermoflava (BVMOFlava) that was successfully expressed in Escherichia coli BL21(DE3). We investigated the activity and stability of the purified enzyme and assigned the substrate profile for structurally different cyclohexanones and cyclobutanones. The enzyme showed lower activity in comparison to cyclohexanone monooxygenase (CHMOAcineto) from Acinetobacter sp. as the prototype BVMO but indicated higher kinetic stability by showing 2-fold increased half-life at 30 °C. The thermodynamic stability, represented by the melting temperature, resulted in a Tm value of 53.1 °C for BVMOFlava that is comparable to the Tm of TmCHMO (ΔTm = 1°C) and significantly higher than the Tm value for CHMOAcineto ((ΔTm = 14.6°C)). We observed a strong deviation between the thermodynamic and the kinetic stability of BVMOFlava, which might has ...
Source: Chembiochem - Category: Biochemistry Authors: Tags: Chembiochem Source Type: research