Arylmalonate Decarboxylase—A Versatile Biocatalyst for the Synthesis of Optically Pure Carboxylic Acids

Bacterial arylmalonate decarboxylase (AMDase) is an intriguing cofactor-independent enzyme with a broad substrate spectrum. Particularly, the highly stereoselective transformation of diverse arylmalonic acids into the corresponding chiral α-arylpropionates has contributed to the broad recognition of this biocatalyst. While, more than 30 years after its discovery, the native substrate and function of AMDase still remain undiscovered, contributions from multiple fields have ever since brought forth a powerful collection of AMDase variants to access a wide variety of optically pure α-substituted propionates. This review aims at providing a comprehensive overview of the development of AMDase from an enzyme with unknown function up to a powerful tailored biocatalyst for the synthesis of industrially relevant optically pure α-arylpropionates. Historical perspectives as well as recent achievements in the field will be covered within this work.

Immobilization of Arylmalonate Decarboxylase

Arylmalonate decarboxylase (AMD) is a monomeric enzyme of only 26 kDa. A recombinant AMDase from Bordetella bronchiseptica was expressed in Escherichia coli and the enzyme was immobilized using different techniques: entrapment in polyvinyl alcohol (PVA) gel (LentiKats®), covalent binding onto magnetic microparticles (MMP, PERLOZA s.r.o., Lovosice, Czech Republic) and double-immobilization (MMP-LentiKats®) using the previous two methods. The double-immobilized AMDase was stable in 8 repeated biocatalytic reactions. This combined immobilization technique has the potential to be applied to different small proteins.

Reaction engineering of biocatalytic (S)-naproxen synthesis integrating in-line process monitoring by Raman spectroscopy

Biocatalytic (S)-naproxen synthesis using an (S)-selective arylmalonate decarboxylase mutant (AMDase G74C/M159L/C188G/V43I/A125P/V156L, AMDase-CLGIPL) exposes a promising environmentally friendly alternative to conventional chemical synthesis strategies.