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IVES 9 IVES Conference Series 9 WAC 9 WAC 2022 9 3 - WAC - Oral 9 Brettanomyces bruxellensis, born to live

Brettanomyces bruxellensis, born to live

Abstract

The wine spoilage yeast Brettanomyces bruxellensis can be found at several steps in the winemaking process due to its resistance to multiple stress conditions. Among the resistance strategies, one could be the formation of biofilm, a lifestyle known to enhance persistence of microorganisms. In this study, we propose to characterize biofilm of B. bruxellensis in wine, especially through several microscopic analyses.

The capacity of the yeast to colonize supports was demonstrated, notably in wine. When biofilms developed on stainless steel chips were inoculated in wine, a considerable cell release from chip into wine was induced, followed by a growth of planktonic cells able to produce wine spoilage metabolites, such as 4-ethylphenol.

Besides the ability to form biofilm, B. bruxellensis is also able to display different cell morphologies, as demonstrated by microscopic observations. First, filaments were observed, playing a role in the structure of biofilm. For the first time, chlamydospore-like was described in this species, probably a potential additional resistance strategy. In addition, a polymorphism of vegetative cells was revealed. Using image analysis, we have shown that strains having different genotyping presented different morphology. Based on this link, a deep learning method was adapted to predict the genetic group of a strain from a simple microscopic observation.

Taken together, all of these features and strategies lead B. bruxellensis to persist in environment and to contaminate wine. Moreover, morphology of vegetative cells could be newly considered as indicator of a strain resistance capacity since the sensitivity to SO2 depend on the strain genetic group.

DOI:

Publication date: June 13, 2022

Issue: WAC 2022

Type: Article

Authors

Manon LEBLEUX, Emmanuel Denimal, Hany ABDO, Christian COELHO, Louise Basmaciyan, Hervé Alexandre, Stéphanie Weidmann, Sandrine ROUSSEAUX

Presenting author

Manon LEBLEUX – Université Bourgogne Franche-Comté, AgroSup Dijon, PAM UMR A 02.102 Dijon-France. Laboratoire VAlMiS-IUVV

Agrosup Dijon, Direction Scientifique, Appui A La Recherche, 26 Boulevard Docteur Petitjean, Dijon, F-21000, France, Laboratoire Valmis-IUVV | Université Bourgogne Franche-Comté, Agrosup Dijon, PAM UMR A 02.102 Dijon-France. Laboratoire PCAV | Université Bourgogne Franche-Comté, Agrosup Dijon, PAM UMR A 02.102 Dijon-France. Laboratoire Valmis-IUVV

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Keywords

Brettanomyces bruxellensis – wine spoilage – biofilm – morphology – deep learning

Tags

IVES Conference Series | WAC 2022

Citation

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