Biocatalysis

In order to accelerate (catalyse) chemical processes, live (biological) systems or their components are used in biocatalysis. In biocatalytic processes, organic substances are chemically transformed by natural catalysts like enzymes. Enzymes that have been mostly separated and enzymes that are still found inside live cells are both used for this purpose. The ability to produce altered or artificial enzymes is a result of contemporary biotechnology, especially guided evolution. This has made it feasible to create enzymes that might facilitate new small molecule conversions that could otherwise be challenging or unattainable using conventional synthetic organic chemistry. Chemoenzymatic synthesis refers to the use of natural or altered enzymes to carry out organic synthesis; the reactions carried out by the enzyme are categorised as chemoenzymatic reactions. Biocatalysis has recently included photoredox catalysis, opening up novel, previously unattainable reactions. Light is required for the production of free radical intermediates in photoredox chemistry. When there is no external chiral environment present, racemic mixtures of the product are produced because these radical intermediates are achiral. In the active site, enzymes can create this chiral environment, fix a certain conformation, and promote the synthesis of a single, enantiopure product. There are two types of photoredox-enabled biocatalysis reactions:

- An external photocatalyst

- An inside coenzyme/cofactor photocatalyst