Biocatalytic Cascade Concepts

Using these two groups of multienzymatic systems as a basis, tiiere have been several attempts to classify such cascade reaction schemes [19, 24]. Three basic cascade schemes can be distinguished, namely, (1) linear, (2) parallel and cyclic, and (3) orthogonal. The motivation for implementahon in each case is a little different  

Examples of cascade schemes for two-enzyme combinations, (a) Linear, (b) Parallel, (c) Cyclic, (d) Orthogonal. E., E represent enzymes 1,1, 1 represent intermediates P, P. P represent products and S, S., S2 represent substrates. 

TABLE 20.1 Rationale for Implementation of Different Cascade Types  

Linear Addition of preceding step Added value of reaction scheme 

Parallel Cofactor self-sufficiency Reduce cofactor costs 

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Much progress has been made using the concepts described in the previous section to implement new biocatalytic cascades. The vast majority of these have been examined at laboratory scale, but the following list gives a representative picture of the current state of the art. The cascades are divided into classes, according to the definitions described earlier. 

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