Biocatalysis might effectively address the challenges associated with green and sustainable chemical synthesis. In the work described in this thesis, native and newly engineered enzymes were used for the step-economic and more sustainable biocatalytic synthesis of valuable precursors to pharmaceuticals and nutraceuticals, including enantioenriched epoxides, vicinal triols and amino acids. First, a non-natural aldolase and a non-natural peroxygenase, both evolved in the laboratory from the promiscuous enzyme 4-oxalocrotonate tautomerase, were combined to develop a one-pot two-step enzymatic cascade for the preparation of α,β-epoxy-aldehydes. The addition of a specifically selected natural epoxide hydrolase to the same pot yielded a short pathway to enantioenriched aryl glycerols from simple biomass-derived starting materials. Second, the laboratory evolution of the enzyme ethylenediamine-N,N'-disuccinic acid (EDDS) lyase generated an enzyme variant that showed a large improvement in activity, enabling the effective and enantioselective synthesis of complex L-aspartic acid derivatives, valuable precursors to the artificial dipeptide sweeteners neotame and advantame. These results present new opportunities to develop practical multienzymatic processes for the more sustainable and step-economic synthesis of an important class of food additives. Finally, a study into the structure, mechanism and biocatalytic potential of a newly discovered monooxygenase, named Rhop3, is presented.
|Qualification||Doctor of Philosophy|
|Place of Publication||[Groningen]|
|Publication status||Published - 2023|