53584-56-8Relevant articles and documents
α-Hydroxy-β-keto acid rearrangement-decarboxylation: Impact on thiamine diphosphate-dependent enzymatic transformations
Beigi, Maryam,Loschonsky, Sabrina,Lehwald, Patrizia,Brecht, Volker,Andrade, Susana L.A.,Leeper, Finian J.,Hummel, Werner,Müller, Michael
, p. 252 - 256 (2013)
The thiamine diphosphate (ThDP) dependent MenD catalyzes the reaction of α-ketoglutarate with pyruvate to selectively form 4-hydroxy-5-oxohexanoic acid 2, which seems to be inconsistent with the assumed acyl donor role of the physiological substrate α-KG. In contrast the reaction of α-ketoglutarate with acetaldehyde gives exclusively the expected 5-hydroxy-4-oxo regioisomer 1. These reactions were studied by NMR and CD spectroscopy, which revealed that with pyruvate the observed regioselectivity is due to the rearrangement-decarboxylation of the initially formed α-hydroxy-β-keto acid rather than a donor-acceptor substrate role variation. Further experiments with other ThDP-dependent enzymes, YerE, SucA, and CDH, verified that this degenerate decarboxylation can be linked to the reduced enantioselectivity of acyloins often observed in ThDP-dependent enzymatic transformations.
An artificial enzymatic reaction cascade for a cell-free bio-system based on glycerol
Gao, Chao,Li, Zhong,Zhang, Lijie,Wang, Chao,Li, Kun,Ma, Cuiqing,Xu, Ping
supporting information, p. 804 - 807 (2015/03/04)
Conversion of glycerol into high-value products is of significant importance for sustainability in the biofuel industry. In this study, pyruvic acid, a central intermediate needed for the production of versatile biomolecules, was produced from glycerol without the addition of any cofactors by the cell-free bio-system composed of alditol oxidase, dihydroxy acid dehydratase, and catalase. (3R)-Acetoin was then produced at 85.5% of the theoretical yield from glycerol by α-acetolactate synthase and α-acetolactate decarboxylase. Since other biomolecules can also be produced from pyruvic acid, the cell-free bio-system might serve as a versatile bio-production platform, and support the viability of the biofuel economy. This journal is
Enantioselective enzymatic synthesis of the α-hydroxy ketone (R)-acetoin from meso-2,3-butanediol
Kochius, Svenja,Paetzold, Melanie,Scholz, Alexander,Merkens, Hedda,Vogel, Andreas,Ansorge-Schumacher, Marion,Hollmann, Frank,Schrader, Jens,Holtmann, Dirk
, p. 61 - 66 (2014/05/20)
Acetoin (3-hydroxy-2-butanone) is an important flavour compound and is applied in cosmetics, pharmacy and chemical synthesis. In contrast to chemical syntheses or fermentations an enzymatic route facilitates enantioselective acetoin production. The discovery of a (S)-selective alcohol dehydrogenase enables a novel production process of (R)-acetoin from meso-2,3-butanediol. It was shown that the regeneration of oxidised nicotinamide adenine dinucleotide is a key point in preparative application of dehydrogenases for the oxidative route. An electrochemical regeneration system was successful combined with the ADH catalysed reaction. Up to 48 mM (R)-acetoin was produced in the reaction system while productivities up to 2 mM h-1 were reached. The possibility to apply an electrochemical system in a semi-preparative synthesis will stimulate further research of electroenzymatic processes with oxidoreductases.
