Enantiomerically pure amines have a variety of industrial applications. They are valuable components within the pharmaceutical and agrochemical industry, resolving agents for separation of racemic mixtures by dimeric salt formation and ligands for transition metal catalysts and chemocatalysts. Biocatalysis is increasingly seen as the method of choice for the synthesis of chiral amines. New commercial enzymes being readily available and new screening/evolution technologies allow for enzyme optimisation towards a set of required conditions for chiral amine synthesis. Transaminases are a class of pyridoxal 5'-phosphate (PLP) dependant enzymes that catalyse the reversible transfer of ammonia from an amine donor (e.g. alanine) to a keto acceptor (e.g. acetophenone), allowing the potential for asymmetric methodologies. Transaminases are already well established for the industrial production of alpha-amino acids and now that research scientists have dealt with some of the problems with equilibrium and substrate/product inhibition, they are being investigated for the industrial application of chiral amines. A multi-enzyme kinetic assay has been utilised for characterisation of newly identified transaminase enzymes in solution phase. Identified transaminases that showed desirable characteristics were cloned and expressed and utilised in the synthesis of amines of interest to industry. Dual enzyme cascade reactions utilising transaminases and either galactose oxidase from Fusarium sp. or monoamine oxidase from Aspergillus niger were used to produce a number of primary and secondary amines in high e.e. and conversion.
|Date of Award||31 Dec 2013|
- The University of Manchester
|Supervisor||Nicholas Turner (Supervisor)|
- Transaminase, biocatalysis, amines, chiral, ketones