Cascade Biocatalytic Processes through Combined Cross-linked Enzyme Aggregates

Cascade reactions catalyzed by immobilized multi enzymatic systems are emerging as a tool to address the increasing need for green and sustainable chemistry. In this regard, the carrier-free immobilization strategy of combined cross-linked enzymes aggregates (combi- CLEAs) is of great interest. In a combi-CLEAs two or more enzymes are co-immobilized into a single unit where they are accommodated in close proximity in order to minimize the intermediates diffusion in the reaction medium, at the same time allowing the access of substrates and coenzymes to the active sites. The use of CLEAs provides a simple and low cost methodology that enhances operational and storage enzyme stability and facilitates biocatalyst recovery and recycle. Some significant applications of cascade reactions catalyzed by combi- CLEAs are reported in this mini-review. These examples have been applied on a multigram scale and have furnished practical steps towards the implementation of enzymes on an industrial scale.