Purification and characterization of a p-coumarate decarboxylase and a vinylphenol reductase from Brettanomyces bruxellensis
The presence of Brettanomyces bruxellensis has been correlated with an increase of phenolic aromas in wine. The production of these aromas results from the metabolization of cinnamic acids, present in the wine, to their ethyl derivatives. Hence, the participation of two enzymes has been proposed: a p-coumarate decarboxylase (CD) and a vinylphenol reductase (VR). Both enzymes were purified and characterized from B. bruxellensis. In denaturing conditions, the CD enzyme had a molecular mass of 21Â kDa, while in native conditions its mass was 41Â kDa. The optimal activity was obtained at a temperature of 40Â Â°C and a pH of 6.0. For p-coumaric acid, the Km value and Vmax were 1.22 Â± 0.08Â mM and 98 Â± 0.15Â Î¼mol/min mg, respectively. The VR enzyme had a molecular mass of 37Â kDa in SDS-PAGE, while in natural conditions its mass was 118Â kDa. The Km value was > 3.37 Â± 2.05Â mM and its Vmax was 107.62 Â± 50.38Â Î¼mol/min mg for NADPH used as a cofactor. Both enzymatic activities were stable at pH 3.4, but in the presence of ethanol the CD activity decreased drastically while the VR activity was more stable. This is the first report that shows the presence of a CD and a VR enzyme in B. bruxellensis. Â© 2008 Elsevier B.V. All rights reserved.
|Título según WOS:||Purification and characterization of a p-coumarate decarboxylase and a vinylphenol reductase from Brettanomyces bruxellensis|
|Título según SCOPUS:||Purification and characterization of a p-coumarate decarboxylase and a vinylphenol reductase from Brettanomyces bruxellensis|
|Título de la Revista:||INTERNATIONAL JOURNAL OF FOOD MICROBIOLOGY|
|Fecha de publicación:||2008|
|Página de inicio:||6|