Compartmentalized cross-linked enzyme nano aggregates (-CLEAs) toward pharmaceutical transformations.

A new immobilization strategy using compartmentalized nanoreactors is herein reported for two biocatalytic processes: (1) -acetylneuraminate lyase (NAL) is internalized in NAL--CLEAs and used in a continuous flow aldol condensation of -acetyl-d-mannosamine with sodium pyruvate to -acetylneuraminic acid; (2) two hydroxysteroid dehydrogenases (HSDH) 7α- and 7β-HSDH are incorporated in -CLEAs and used in a two-step cascade batch synthesis of ursodeoxycholic acid (UDCA). The versatile use of -CLEA demonstrates that this immobilization methodology is a valuable addition to the toolbox of synthetic chemists.