1956-15-6Relevant articles and documents
Bi-enzymatic Conversion of Cinnamic Acids to 2-Arylethylamines
Weise, Nicholas J.,Thapa, Prasansa,Ahmed, Syed T.,Heath, Rachel S.,Parmeggiani, Fabio,Turner, Nicholas J.,Flitsch, Sabine L.
, p. 995 - 998 (2020/01/21)
The conversion of carboxylic acids, such as acrylic acids, to amines is a transformation that remains challenging in synthetic organic chemistry. Despite the ubiquity of similar moieties in natural metabolic pathways, biocatalytic routes seem to have been overlooked for this purpose. Herein we present the conception and optimisation of a two-enzyme system, allowing the synthesis of β-phenylethylamine derivatives from readily-available ring-substituted cinnamic acids. After characterisation of both parts of the reaction in a two-step approach, a set of conditions allowing the one-pot biotransformation was optimised. This combination of a reversible deaminating and irreversible decarboxylating enzyme, both specific for the amino acid intermediate in tandem, represents a general method by which new strategies for the conversion of carboxylic acids to amines could be designed.
Phenylalanine ammonia lyase catalyzed synthesis of amino acids by an MIO-cofactor independent pathway
Lovelock, Sarah L.,Lloyd, Richard C.,Turner, Nicholas J.
, p. 4652 - 4656 (2014/05/20)
Phenylalanine ammonia lyases (PALs) belong to a family of 4-methylideneimidazole-5-one (MIO) cofactor dependent enzymes which are responsible for the conversion of L-phenylalanine into trans-cinnamic acid in eukaryotic and prokaryotic organisms. Under conditions of high ammonia concentration, this deamination reaction is reversible and hence there is considerable interest in the development of PALs as biocatalysts for the enantioselective synthesis of non-natural amino acids. Herein the discovery of a previously unobserved competing MIO-independent reaction pathway, which proceeds in a non-stereoselective manner and results in the generation of both L- and D-phenylalanine derivatives, is described. The mechanism of the MIO-independent pathway is explored through isotopic-labeling studies and mutagenesis of key active-site residues. The results obtained are consistent with amino acid deamination occurring by a stepwise E1cB elimination mechanism. All manner of things: A competing MIO-independent (MIO=4-methylideneimidazole-5-one) reaction pathway has been identified for phenylalanine ammonia lyases (PALs), which proceeds in a non-stereoselective manner, resulting in the generation of D-phenylalanine derivatives. The mechanism of D-amino acid formation is explored through isotopic-labeling studies and mutagenesis of key active-site residues.
Enantioselective synthesis of non-natural amino acids using phenylalanine dehydrogenases modified by site-directed mutagenesis
Busca, Patricia,Paradisi, Francesca,Moynihan, Eamonn,Maguire, Anita R.,Engel, Paul C.
, p. 2684 - 2691 (2007/10/03)
The substrate scope of three mutants of phenylalanine dehydrogenase as biocatalysts for the transformation of a series of 2-oxo acids, structurally related to phenylpyruvic acid, to the analogous -amino acids, non-natural analogues of phenylalanine, has been investigated. The mutant enzymes are more tolerant than the wild type enzyme of the non-natural substrates, especially those with substituents at the 4-position on the phenyl ring. Excellent enantiocontrol resulted in all cases.