Multienzyme System Construction and Multienzyme Catalytic Conversion

Enzymes have great application potential in many industrial sectors due to their high activity, high selectivity and specificity under mild conditions. Nevertheless, majority studies relevant to enzymatic catalysis have been carried out by using single enzyme. As a matter of fact, living organisms manipulate a huge variety of multienzymatic cascade reactions in a common reaction medium–the cytosol. In recent years, multienzyme cascade reaction has evolved as an important research area in biocatalysis and bioconversion. More recently, the multienzyme catalyzed processes has been regarded as “the next generation of biocatalysis”. However, multienzymes in free form cannot fulfill the economic requirements of an industrial biocatalysis. Therefore, design of new immobilization supports and protocols to construct stable and recyclable multienzyme system will represent an important research branch.

Compared with other approaches for multienzyme system construction under relatively harsh conditions, we focus on the biomimetic and bioinspired strategies to construct multienzyme system under aqueous phase, ambient temperature and neutral pH. These strategies include biomimetic mineralization, bioadhesion and their combination. Specifically, (I) through biomimetic mineralization strategy, multienzyme systems based on nanoparticle, microcapsule with single or two compartments as well as capsules-in-bead scaffold have been synthesized; (II) inspired by the multifunctional properties of adhesive proteins from mussel, an alternative approach enabled by polydopamine has been developed for the construction of microcapsule-based-multienzyme system; (III) through the strategy combining biomimetic mineralization and bioadhesion platforms, robust multienzyme system based on organic–inorganic hybrid microcapsule has been constructed. Order-of-magnitude product yield enhancement and desirable stability property (including pH, temperature, storage and recycling stability) are demonstrated when these multienzyme systems are employed for the conversion of carbon dioxide to formaldehyde/methanol or the conversion of starch to oligosaccharide.

In the future, multienzyme catalytic conversion will replace many existing chemically catalyzed processes. Meanwhile, multienzyme system construction and multienzyme catalytic conversion will remain as one of the crucial and hot issues.