Functional analysis to identify genes in wine yeast adaptation to low-temperature fermentation

Abstract

Aims: To identify genes and proteins involved in adaptation to low‐temperature fermentations in a commercial wine yeast. Methods and Results: Nine proteins were identified as representing the most significant changes in proteomic maps during the first 24 h of fermentation at low (13°C) and standard temperature (25°C). These proteins were mainly involved in stress response and in glucose and nitrogen metabolism. Transcription analysis of the genes encoding most of these proteins within the same time frame of wine fermentation presented a good correlation with proteomic data. Knockout and overexpressing strains of some of these genes were constructed and tested to evaluate their ability to start the fermentation process. The strain overexpressing ILV5 improved its fermentation activity in the first hours of fermentation. This strain showed a quicker process of mitochondrial degeneration, an altered intracellular amino acid profile and laxer nitrogen catabolite repression regulation. Conclusions: The proteomic and transcriptomic analysis is useful to detect key molecular adaptation mechanisms of biotechnological interest for industrial processes. ILV5 gene seems to be important in wine yeast adaptation to low‐temperature fermentation. Significance and Impact of the Study: This study provides information that might help improve the future performance of wine yeast, either by genetic modification or by adaptation during industrial production.

Transcriptional response of Saccharomyces cerevisiae to low temperature during wine fermentation

“…Only four of these genes were differentially regulated at low temperature in our data (HSP12, NSR1, RPL2B, TIR2). Salvadó et al (2012) identified ILV5 as important for the adaptation of wine yeast to low temperature fermentation; however, unlike Salvadó et al (2012), we did not see any transcriptional change in ILV5. It appears that the response to cold temperature may be strongly influenced by strain, medium and exact temperature used.…”

Metabolomic Comparison of Saccharomyces cerevisiae and the Cryotolerant Species S. bayanus var. uvarum and S. kudriavzevii during Wine Fermentation at Low Temperature

“…In a proteomic study of the response of the same wine yeast at low temperature, Salvadó et al . [30] also detected a higher concentration of Yhb1 (Yeast hemoglobin-like protein), with functions in oxidative stress response.…”

“…A metabolome analysis is a powerful tool to understand metabolic changes in response to different environmental conditions, such as cold temperatures. In past years, some attempts have been made to elucidate the cold response of the same wine yeast Sc using a variety of high-throughput methodologies, such as transcriptomics [21] or proteomics [30]. These metabolic changes could be due to temperature-mediated transcriptional and/or to post-transcriptional effects on yeast.…”

Biotechnological impact of stress response on wine yeast

“…Hsp26, together with Hsp12, is also induced at the protein level when low‐temperature wine fermentation is carried out (Salvado et al . ). Therefore, chaperones like Hsp26 are good molecular markers that mark stress under many biotechnological conditions.…”