Integrating transcriptomics and metabolomics for the analysis of the aroma profiles of Saccharomyces cerevisiae strains from diverse origins

Abstract

BackgroundDuring must fermentation thousands of volatile aroma compounds are formed, with higher alcohols, acetate esters and ethyl esters being the main aromatic compounds contributing to floral and fruity aromas. The action of yeast, in particular Saccharomyces cerevisiae, on the must components will build the architecture of the wine flavour and its fermentation bouquet. The objective of the present work was to better understand the molecular and metabolic bases of aroma production during a fermentation process. For such, comparative transcriptomic and metabolic analysis was performed at two time points (5 and 50 g/L of CO2 released) in fermentations conducted by four yeast strains from different origins and/or technological applications (cachaça, sake, wine, and laboratory), and multivariate factorial analyses were used to rationally identify new targets for improving aroma production.ResultsResults showed that strains from cachaça, sake and wine produced higher amounts of acetate esters, ethyl esters, acids and higher alcohols, in comparison with the laboratory strain. At fermentation time T1 (5 g/L CO2 released), comparative transcriptomics of the three S. cerevisiae strains from different fermentative environments in comparison with the laboratory yeast S288c, showed an increased expression of genes related with tetracyclic and pentacyclic triterpenes metabolism, involved in sterol synthesis. Sake strain also showed upregulation of genes ADH7 and AAD6, involved in the formation of higher alcohols in the Ehrlich pathway. For fermentation time point T2 (50 g/L CO2 released), again sake strain, but also VL1 strain, showed an increased expression of genes involved in formation of higher alcohols in the Ehrlich pathway, namely ADH7, ADH6 and AAD6, which is in accordance with the higher levels of methionol, isobutanol, isoamyl alcohol and phenylethanol observed.ConclusionsOur approach revealed successful to integrate data from several technologies (HPLC, GC-MS, microarrays) and using different data analysis methods (PCA, MFA). The results obtained increased our knowledge on the production of wine aroma and flavour, identifying new gene in association to the formation of flavour active compounds, mainly in the production of fatty acids, and ethyl and acetate esters.Electronic supplementary materialThe online version of this article (doi:10.1186/s12864-017-3816-1) contains supplementary material, which is available to authorized users.

Transcriptome Profile of Yeast Strain Used for Biological Wine Aging Revealed Dynamic Changes of Gene Expression in Course of Flor Development

“…It is well known and shown in numerous studies using both microarray and RNA-seq platforms that transcriptional responses of yeast strains to different environmental cues are highly variable depending on the nature of abusing agent, time of exposure, strain genotype etc. (Taymaz-Nikerel et al, 2016;Ibáñez et al, 2017;Mendes et al, 2017;Tondini et al, 2019). It is also necessary to distinguish short and long-term responses and acquired resistance as mechanisms of adaptation (Stanley et al, 2010).…”

Symposium review: Genomic investigations of flavor formation by dairy microbiota

“…As such, small changes in the population dynamics can have a dramatic effect on metabolism and, in turn, flavor production. Recently, integrated approaches have examined flavor production in a variety of mixed-culture systems or microbial communities, including the combination of metagenomics and flavor analyses in the study of a complex multispecies solid-state fermentation as occurs in acetic acid fermentation (Wang et al, 2016), and the successful integration of metabolomic and transcriptomic data for the analysis of flavor profiles generated by multiple yeasts during wine fermentation (Mendes et al, 2017), as well as the dairy-based systems discussed previously (Bertuzzi et al, 2018).…”

Grape and Wine Metabolomics to Develop New Insights Using Untargeted and Targeted Approaches

“…This integrated approach is still under-utilized in grape and wine research compared to other food and agricultural sectors and only few publications can be found. However, a combination of metabolomics and transcriptomics has been adopted to study different wine yeast strains under wine fermentation-like conditions to develop new insights into the role of oxygen impulse on S cerevisiae wine strains [153,154] and to explore the aroma profiles of wines produced by different S cerevisiae strains of diverse origins [155].…”

“…Integration of transcriptomics and metabolomics data can also be used for the generation of new insights into the yeast metabolism and fermentation process, particularly aroma compound development. For instance, Mendes, Sanchez, Franco-Duarte, Camarasa, Schuller, Dequin and Sousa [155] performed a comparative transcriptomics and metabolomics analysis of four yeast strains from diverse origins (e.g., wine, sake, cacha double dagger and laboratory) at two time points. They used a multivariate factorial analysis to identify new markers that can be used for improvement of aroma production.…”

“…The combined omics data allowed them to differentiate all the yeast strains at both the metabolic and transcriptomic level and extended their knowledge on the production of wine aroma and flavor. They also identified new genes associated with the development of flavor active compounds, primarily those related to the production of fatty acids, and ethyl and acetate esters [155].…”