Hydrogen-bonded organic framework biomimetic entrapment allowing non-native biocatalytic activity in enzyme

Abstract

Nature programs the structural folding of an enzyme that allows its on-demand biofunctionality; however, it is still a long-standing challenge to manually modulate an enzyme’s conformation. Here, we design an exogenous hydrogen-bonded organic framework to modulate the conformation of cytochrome c, and hence allow non-native bioactivity for the enzyme. The rigid hydrogen-bonded organic framework, with net-arranged carboxylate inner cage, is in situ installed onto the native cytochrome c. The resultant hydrogen-bonded nano-biointerface changes the conformation to a previously not achieved catalase-like species within the reported cytochrome c-porous organic framework systems. In addition, the preserved hydrogen-bonded organic framework can stabilize the encapsulated enzyme and its channel-like pores also guarantee the free entrance of catalytic substrates. This work describes a conceptual nanotechnology for manoeuvring the flexible conformations of an enzyme, and also highlights the advantages of artificial hydrogen-bonded scaffolds to modulate enzyme activity.

Heme units are immobilised in diverse heme enzymes for oxidation, and have been immobilised also in hydrogen-bonded organic frameworks. Here, the authors show the use of hydrogen-bonded organic framework to modulate the enzyme’s conformation and show different biofunction from the original.