WAC 2022 banner
IVES 9 IVES Conference Series 9 WAC 9 WAC 2022 9 3 - WAC - Oral 9 The wine microbial ecosystem: Molecular interactions between yeast species and evidence for higher order interactions

The wine microbial ecosystem: Molecular interactions between yeast species and evidence for higher order interactions

Abstract

Fermenting grape juice represents one of the oldest continuously maintained anthropogenic microbial environments and supports a well-mapped microbial ecosystem. Several yeast and bacterial species dominate this ecosystem, and some of these species are part of the globally most studied and best understood individual organisms. Detailed physiological, cellular and molecular data have been generated on these individual species and have helped elucidate complex evolutionary processes such as the domestication of wine yeast strains of the species Saccharomyces cerevisiae. These data support the notion that the wine making environment represents an ecological niche of significant evolutionary relevance. Taken together, the data suggest that the wine fermentation ecosystem is an excellent model to study fundamental questions about the working of microbial ecosystems and on the impact of biotic selection pressures on microbial ecosystem functioning. Indeed, and although well mapped, the rules and molecular mechanisms that govern the interactions between microbial species within this, and other, ecosystems remain underexplored. Here we present data derived from several converging approaches, including microbiome data of spontaneous fermentations, the population dynamics of constructed consortia, the application of biotic selection pressures in directed laboratory evolution, and the physiological and molecular analysis of pairwise and higher order interactions between yeast species. The data reveal the importance of cell wall-related elements in interspecies interactions and in evolutionary adaptation and suggest that predictive modelling and biotechnological control of the wine ecosystem during fermentation are promising strategies for wine making in future.

DOI:

Publication date: June 13, 2022

Issue: WAC 2022

Type: Article

Authors

Cleo Conacher, Florian F. Bauer, Natasha Luyt, Bryan K. Mundia, Mathabatha E. Setati, Debra Rossouw

Presenting author

Cleo Conacher | South African Grape and Wine Research Institute, Department of Viticulture and Oenology, Stellenbosch University

South African Grape and Wine Research Institute, Department of Viticulture and Oenology, Stellenbosch University

Contact the author

Keywords

Fermentation ecosystem, dominant yeast species, interactions, consortia, gene expression

Tags

IVES Conference Series | WAC 2022

Citation

Related articles…

ANTI-TRANSPIRANT MODULATION OF GRAPE RIPENING: EFFECTS ON MERLOT VINE DEVELOPMENT AND ROSÉ WINE PHENOLIC AND AROMATIC PROFILES

Climate changes are impacting viticultural regions throughout the world with temperature increases being most prevalent.1 These changes will not only impact the regions capable of growing grapes, but also
the grapes that can be grown.2 As temperatures rise the growing degree days increase and with it the sugar accumulation within the berries and subsequent alcohol levels in wine. Consequently, viticultural
practices need to be examined to decrease the levels of sugars.

Impact of harvest date on the terroir expression and the aroma profile of Touraine Sauvignon wines

L’objectif d’une étude sur trois années vise, pour des terroirs différents et connus pour le profil des vins qui en sont issus, à exploiter au mieux le potentiel des raisins en optimisant la date de récolte ; pour chacun des trois terroirs, les minivinifications sont réalisées à partir de trois dates de récolte . Il s’avère, grâce à un suivi analytique important (sol, précurseurs et arômes) et une caractérisation organoleptique bien encadrée (analyse sensorielle pertinente et objective), que le choix de la date de récolte, en fonction du terroir, a une incidence sur le profil du vin et devient un outil pour l’élaborateur.

Anthropogenic intervention in shaping Terroir in a California Pinot noir vineyard

In many vineyards optimal parcel size exceeds the geospatial complexity that exists in soils and topographic features that influence hydrological properties, sunlight interception and soil depth and texture (available water capacity).

Methodological advances in relating deep root activity to whole vine physiology

Full understanding of grapevine responses to variable soil resources requires
assessing the grapevine root system. Grapevine root systems are expansive and examining deep roots (i.e., >40 cm)
is particularly important in conditions where grapevines increase reliance on deep soil resources, such as drought
or plant competition. Traditional methods of assessing roots rely on morphological traits associated specific
functions (e.g., root color, diameter, length), while recent methodological advances allow for estimating root
function more directly (e.g., omics). Yet, the potential of applying refined methods remains underexplored for roots
at deep depths.

Impact of pruning method on vegetative growth and yield

Over the past fifteen years or so, a number of theories have emerged on more or less new pruning practices.