Improving the Stability of Membrane-Binding Enzymes for the Sustainable Production of Monoterpenes in a MOF-on-aMOF Bifunctional Core–Shell Nanoreactor

It is challenging and extremely complicated to investigate the catalytic performance of integral membrane enzymes in vitro. To address this, here we report a method to enhance the rigidity of integral membrane enzymes and their nanodisc "subunits" by a one-pot coprecipitation process. This process encapsulates the enzyme-nanodisc system within amorphous metal–organic frameworks (aMOFs). The resulting biocomposites exhibited a 1.56 times higher apparent activity and a 26.13 times higher operation stability than the corresponding free enzymes. Preincubation increased the load of integral membrane enzymes in the multishelled aMOF by 2.18 times. Furthermore, the encapsulation of (−)-trans-isopiperitenol dehydrogenase, NAD+, and NADH oxidase in the MOF/aMOF yields a coupled biocatalytic cascade, which catalytically reduces (−)-trans-isopiperitenol to (−)-isopiperitenone with a 17.82-fold higher yield than a bulk mixture of catalysts in solution.