Global distribution of IRC7 alleles in Saccharomyces cerevisiae populations: a genomic and phenotypic survey within the wine clade. (11th May 2021)

• Record Type: Journal Article
• Authors: Ruiz, Javier; de Celis, Miguel; Martín‐Santamaría, María; Benito‐Vázquez, Iván; Pontes, Ana; Lanza, Val F.; Sampaio, José Paulo; Santos, Antonio; Belda, Ignacio
• Is Part Of: Environmental microbiology. Volume 23:Number 6(2021)
• Page Start: 3182
• Page End: 3195
• Publication Date: 2021-05-11
• Subjects: Microbial ecology -- Periodicals; Environmental Microbiology -- Periodicals; 579.17
• DOI: 10.1111/1462-2920.15540
• Languages: English
• ISSNs: 1462-2912

Abstract

Summary: The adaptation to the different biotic and abiotic factors of wine fermentation has led to the accumulation of numerous genomic hallmarks in Saccharomyces cerevisiae wine strains. IRC7, a gene encoding a cysteine‐S‐β‐lyase enzyme related volatile thiols production in wines, has two alleles: a full‐length allele ( IRC7 F ) and a mutated one ( IRC7 S ), harbouring a 38 bp‐deletion. Interestingly, IRC7 S ‐encoding a less active enzyme – appears widespread amongst wine populations. Studying the global distribution of the IRC7 S allele in different yeast lineages, we confirmed its high prevalence in the Wine clade and demonstrated a minority presence in other domesticated clades (Wine‐PDM, Beer and Bread) while it is completely missing in wild clades. Here, we show that IRC7 S ‐homozygous (HS) strains exhibited both fitness and competitive advantages compared with IRC7 F ‐homozygous (HF) strains. There are some pieces of evidence of the direct contribution of the IRC7 S allele to the outstanding behaviour of HS strains (i.e., improved response to oxidative stress conditions and higher tolerance to high copper levels); however, we also identified a set of sequence variants with significant co‐occurrence patterns with the IRC7 S allele, which can be co‐contributing to the fitness and competitive advantages of HS strains in wine fermentations.