Open AccessEffects ofADH2Overexpression inSaccharomyces bayanusduring Alcoholic Fermentation
Author(s) -
Oscar Maestre,
Teresa GarcíaMartínez,
Rafael A. Peinado,
Juan Carlos Mauricio
Publication year - 2008
Publication title -
applied and environmental microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.552
H-Index - 324
eISSN - 1070-6291
pISSN - 0099-2240
DOI - 10.1128/aem.01805-07
Subject(s) - ethanol fermentation , fermentation , saccharomyces , food science , saccharomyces cerevisiae , biology , yeast , chemistry , genetics
The effect of overexpression of the geneADH2 on metabolic and biological activity inSaccharomyces bayanus V5 during alcoholic fermentation has been evaluated. This gene is known to encode alcohol dehydrogenase II (ADH II). During the biological aging of sherry wines, where yeasts have to grow on ethanol owing to the absence of glucose, this isoenzyme plays a prominent role by converting the ethanol into acetaldehyde and producing NADH in the process. Overexpression of the geneADH2 during alcoholic fermentation has no effect on the proteomic profile or the net production of some metabolites associated with glycolysis and alcoholic fermentation such as ethanol, acetaldehyde, and glycerol. However, it affects indirectly glucose and ammonium uptakes, cell growth, and intracellular redox potential, which lead to an altered metabolome. The increased contents in acetoin, acetic acid, andl -proline present in the fermentation medium under these conditions can be ascribed to detoxification by removal of excess acetaldehyde and the need to restore and maintain the intracellular redox potential balance.