Capsules-in-bead scaffold: a rational architecture for spatially separated multienzyme cascade system

A novel kind of capsules-in-bead scaffold was developed to construct a spatially separated multienzyme cascade system. More specifically, each enzyme was first encapsulated in a guest microcapsule through the synergy of biomimetic mineralization and layer-by-layer self-assembly; these guest capsules were then encapsulated into a millimeter-scale gel bead (host bead). Such structured scaffold, was validated by the production of methanol from CO2 via three dehydrogenases consisting of formate, formaldehyde, and alcohol dehydrogenases. Compared to the homogeneous multienzyme cascade system where enzymes were all co-encapsulated in a single gel bead, the capsules-in-bead scaffold substantially improved enzymatic activity, recycling and storage stability, thus higher methanol yield was achieved. Hopefully, this study will set an innovative example for the rational design of complex multienzyme cascades and multienzyme microreactor.