A dual substrate kinetic model for cytochrome P450BM3-F87G catalysis: simultaneous binding of long chain aldehydes and 4-fluorophenol

Choose Your Own Adventure: A Comprehensive Database of Reactions Catalyzed by Cytochrome P450 BM3 Variants

Cytochrome P450 BM3 monooxygenase is the topic of extensive research as many researchers have evolved this enzyme to generate a variety of products. However, the abundance of information on increasingly diversified variants of P450 BM3 that catalyze a broad array of chemistry is not in a format that enables easy extraction and interpretation. We present a database that categorizes variants by their catalyzed reactions and includes details about substrates to provide reaction context. This database of >1500 P450 BM3 variants is downloadable and machine-readable and includes instructions to maximize ease of gathering information. The database allows rapid identification of commonly reported substitutions, aiding researchers who are unfamiliar with the enzyme in identifying starting points for enzyme engineering. For those actively engaged in engineering P450 BM3, the database, along with this review, provides a powerful and user-friendly platform to understand, predict, and identify the attributes of P450 BM3 variants, encouraging the further engineering of this enzyme.

Enhanced 4-FP removal with MnFe2O4 catalysts under dielectric barrier discharge plasma: Economical synthesis, catalytic performance and degradation mechanism

The dielectric barrier discharge plasma (DBDP) process has received extensive attention for the removal of organic contaminants from water. A novel microwave-assisted hydrothermal method was used to easily and rapidly synthesize MnFe₂O₄ catalysts. Based on the DBDP process, MnFe₂O₄ can enhance 4-fluorophenol (4-FP) abatement from 44.15% to 58.78% through the catalysis within 18 min. Then, the adjunction of O₃ generated by discharge can further boost 4-FP degradation to 94.94%. After the whole optimization process is complete, the associated pseudo-first-order reaction kinetic constant and energy efficiency were enhanced from 0.0327 to 0.1536 min^-1 and 2067.13 mg kW h^-1 to 4444.75 mg kW h^-1, respectively. With the help of the condition, blank and radical capture experiments, the catalytic performance caused by MnFe₂O₄ and O₃ was attributed to the joint action of Fenton-like reactions, photocatalysis (ultraviolet, UV), photoassisted Fenton reactions and O₃ catalysis. The overall downward trend of the possible intermediate toxicities indicated that the DBDP/MnFe₂O₄/O₃ process can effectively remove and mineralize 4-FP without the generation of more toxic intermediates. In addition, during the 5 cycles, MnFe₂O₄ can maintain excellent recovery, efficiency and durability. In summary, the coupling of discharge plasma and MnFe₂O₄ sheds new light on catalysis for wastewater treatment.

Control of stereoselectivity of benzylic hydroxylation catalysed by wild-type cytochrome P450BM3 using decoy molecules

The benzylic hydroxylation of non-native substrates was catalysed by cytochrome P450BM3, wherein “decoy molecules” controlled the stereoselectivity of the reactions.