Catalytic Oxidation of Methane by Wild-Type Cytochrome P450BM3 with Chemically Evolved Decoy Molecules

Abstract

Biological methane oxidation is a highly desirable method for the conversion of natural gas into a liquid to meet the increasing demand for fuel and chemical feedstock as well as reducing the potent greenhouse effects of methane emissions. Because natural hemoenzymes that can catalyze the conversion of methane to methanol have not been found, it has long been considered that hemoenzymes, including cytochrome P450s (P450s), cannot catalyze the oxidative conversion of methane. Herein, we report the catalytic oxidation of methane by wild-type P450BM3, without any mutagenesis, in the presence of chemically evolved dummy substrates (decoy molecules) under high-pressure methane at 10 MPa. Our studies showed that methane was catalytically converted into methanol at room temperature with a total turnover number of 4.

Highly selective hydroxylation of gaseous alkanes at the terminal position by wild-type CYP153A33

“…After reaction for 1 h at room temperature, a peak corresponding to 13 CH 3 OH was detected by GCMS analysis, and its TTN reached 0.82, which is lower than that by P450BM3 under similar conditions (TTN = 4.0 for 1 h). 31 Given that the catalytic properties of CYP153A33 differ from those of P450BM3, there may be potential for further improvement of methane hydroxylation efficiencies through the precise optimization of reaction conditions.…”

“…Hydroxylation of 13 C-labeled methane ( 13 CH 4 ) in a high-pressure reactor at 10 MPa 13 C-labeled methane ( 13 CH 4 ) hydroxylation by CYP153A33 was performed based on a procedure for methane hydroxylation by P450BM3. 31 A 13 CH 4 -saturated buffer solution containing CYP153A33, PdR, Pdx (final 1 μM, 5 μM, 10 μM, respectively) and a DMSO solution of decoy molecules (final 100 μM) in 50 mM KPi buffer (pH 7.4) was injected into a high-pressure reaction vessel. Initially, the fluid lines of the reactor were purged with N 2 gas, and then ethane gas was injected into both the reaction vessel and a line connected to the reaction vessel.…”

The Nature of the Chemical Bonds of High-Valent Transition–Metal Oxo (M=O) and Peroxo (MOO) Compounds: A Historical Perspective of the Metal Oxyl–Radical Character by the Classical to Quantum Computations

“…The theoretical reaction profile is consistent with the ET-PT process. This indicates that methane mono-oxygenations may be feasible by the direct evolution [239] and chemical modification (decoy molecules) [214,240] of P450 enzymes.…”

The Versatile Biocatalyst of Cytochrome P450 CYP102A1: Structure, Function, and Engineering

“…Assisted with perfluorinated carboxylic acids as decoy molecules, WT CYP102A1 is capable of oxidizing gaseous alkanes, such as propane and butane, as well as benzene and toluene [ 64 , 65 ]. Recently, WT CYP102A1 was reported to oxidize small gaseous methane to methanol at room temperature at 10 MPa [ 66 ]. It is notoriously difficult to functionalize methane; the small size of methane does not fit well into the active site of CYP102A1.…”