Parallel evolution of the make–accumulate–consume strategy in Saccharomyces and Dekkera yeasts

Saccharomyces yeasts degrade sugars to two-carbon components, in particular ethanol, even in the presence of excess oxygen. This characteristic is called the Crabtree effect and is the background for the 'make–accumulate–consume' life strategy, which in natural habitats helps Saccharomyces yeasts to out-compete other microorganisms. A global promoter rewiring in the Saccharomyces cerevisiae lineage, which occurred around 100 mya, was one of the main molecular events providing the background for evolution of this strategy. Here we show that the Dekkera bruxellensis lineage, which separated from the Saccharomyces yeasts more than 200 mya, also efficiently makes, accumulates and consumes ethanol and acetic acid. Analysis of promoter sequences indicates that both lineages independently underwent a massive loss of a specific cis-regulatory element from dozens of genes associated with respiration, and we show that also in D. bruxellensis this promoter rewiring contributes to the observed Crabtree effect

Impact of volatile phenols and their precursors on wine quality and control measures of Brettanomyces/Dekkera yeasts

Volatile phenols are aromatic compounds and one of the key molecules responsible for olfactory defects in wine. The yeast genus Brettanomyces is the only major microorganism that has the ability to covert hydroxycinnamic acids into important levels of these compounds, especially 4-ethylphenol and 4-ethylguaiacol, in red wine. When 4-ethylphenols reach concentrations greater than the sensory threshold, all wine’s organoleptic characteristics might be influenced or damaged. The aim of this literature review is to provide a better understanding of the physicochemical, biochemical, and metabolic factors that are related to the levels of p-coumaric acid and volatile phenols in wine. Then, this work summarizes the different methods used for controlling the presence of Brettanomyces in wine and the production of ethylphenols

New insights on the features of the vinyl phenol reductase from the wine-spoilage yeast Dekkera/Brettanomyces bruxellensis

Vinyl phenol reductase activity was assayed in extracts from 19 strains of Dekkera bruxellensis isolated from wine. In all strains, vinyl phenol reductase activity was insensitive to the presence/absence of 4-vinyl guaiacol, confirming that expression is not related to the presence of the substrate. D. bruxellensis CBS 4481 showed the highest vinyl phenol reductase activity toward 4-vinyl guaiacol. Vinyl phenol reductase from D. bruxellensis CBS 4481 was purified to mass spectrometric homogeneity, and sequenced by trypsinolysis and mass spectrometry. The sequence of the purified protein showed convincing homology with a Cu/Zn superoxide dismutase in the D. bruxellensisAWRI 1499 genome, and indeed it was found to possess both vinyl phenol reductase and superoxide dismutase activities. A bioinformatics analysis of the sequence of vinyl phenol reductase/superoxide dismutase from D. bruxellensis CBS 4481 reveals the presence in this protein of cofactor-binding structural features, that are absent in sequences of superoxide dismutases from related microorganisms, that do not display vinyl phenol reductase activity