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IVES 9 IVES Conference Series 9 New molecular evidence of wine yeast-bacteria interaction unraveled by untargeted metabolomic profiling

New molecular evidence of wine yeast-bacteria interaction unraveled by untargeted metabolomic profiling

Abstract

Bacterial malolactic fermentation (MLF) has a considerable impact on wine quality. The yeast strain used for primary fermentation can consistently stimulate (MLF+ phenotype) or inhibit (MLF- phenotype) malolactic bacteria and the MLF process as a function of numerous winemaking practices, but the molecular evidence behind still remains a mystery. In this study, such evidence was elucidated by the direct comparison of extracellular metabolic profiles of MLF+ and MLF- yeast phenotypes. Untargeted metabolomics combining ultrahigh-resolution FT-ICR-MS analysis, powerful machine learning methods and a comprehensive wine metabolite database, discovered around 800 putative biomarkers and 2500 unknown masses involved in phenotypic distinction. For the putative biomarkers, we also developed a biomarker identification workflow and elucidated the exact structure (by UPLC-Q-ToF-MS2) and/or exact physiological impact (by in vivo tests) of several novel biomarkers, such as gluconic acid, citric acid, caffeic acid-sulfate, palmitic acid and tripeptide Pro-Phe-Val. In addition to new biomarkers, molecular evidence was reflected by unprecedented chemical diversity (more than 3000 discriminant masses) that characterized MLF+ and MLF- phenotypes. Distinct chemical families such as phenolic compounds, carbohydrates, amino acids and peptides characterize the extracellular metabolic profiles of the MLF+ phenotype, whereas the MLF- phenotype is associated with sulphur-containing peptides. Moreover, the location of MLF+ biomarkers in the yeast metabolic network indicated the potential involvement of specific pathways in MLF stimulation. The untargeted approach used in this study played a significant role in discovering new and unexpected molecular evidence of wine yeast-bacteria interaction.

This work will appear in the accepted article in Metabolomics (Volume 12 issue 5). (http://link.springer.com/journal/11306).

Publication date: May 17, 2024

Issue: Macrowine 2016

Type: Article

Authors

Youzhong Liu*, Cedric Longin, Claudine Degueurce, Hervé Alexandre, Magali Deleris-Bou, Marianna Lucio, Mourad Harir, Philippe Schmitt-Kopplin, Régis Gougeon, Sara Forcisi, Sibylle Dr. Krieger-Weber

*Université de Bourgogne

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Tags

IVES Conference Series | Macrowine | Macrowine 2016

Citation

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