Development of a High‐Pressure Reactor Based on Liquid‐Flow Pressurisation to Facilitate Enzymatic Hydroxylation of Gaseous Alkanes

Abstract

The front cover artwork for Issue 19/2019 is provided by Shoji and co‐workers at Nagoya University (Japan). The image shows the concept of their novel high‐pressure reactor which compresses gaseous alkanes by pumping liquid forcibly (the person wearing a T‐shirt) into the reaction vessel without an exit (the trunk), and pressurizes up to 10 MPa. See the Communication itself at https://doi.org/10.1002/cctc.201901323.

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

“…The ratio of 13 CH 3 OH/ 12 CH 3 OH exceeded 2%, indicating that generated 13 CH 3 OH originated from the direct hydroxylation of 13 CH 4 . Taking into account the maximum TOF of ethane (83 min –1 ) and propane (2200 min –1 ) in our reaction system, the observed TOF value for methane hydroxylation (0.067 min –1 estimated from the TTN) is lower than what would be expected when assuming a proportional relationship between the BDE and activity. This suggests that the relationship between BDE and TOF is close to the reported non-linear relationship. , When N 2 or 12 CH 4 was employed instead of 13 CH 4 , no appreciable amount of 13 CH 3 OH originating from methane hydroxylation could be detected.…”

“…13 C-labeled methane ( 13 CH 4 ) hydroxylation by P450BM3 was performed based on the procedure of ethane hydroxylation with several optimizations for methane hydroxylation …”

“…Initially, methane hydroxylation was performed under atmospheric pressure (0.1 MPa) for 1 h with each of the top six decoy molecules discovered in the bromomethane assays; however, significant 13 CH 3 OH generation could not be detected. Subsequently, reaction trials were repeated by applying a high-pressure of 13 CH 4 (1 or 10 MPa) in a HPLC-based high-pressure reactor developed by our research group, 46,50 wherewith the NADPH solution can be added to the reaction mixture after pressurization, leading to a reduction in undesirable uncoupling by P450BM3. Employing this technology, an appreciable amount of 13 CH 3 OH originating from methane hydroxylation by wild-type P450BM3 could be detected under 10 MPa of 13 CH 4 .…”