DOI: 10.5061/dryad.ps441
title: Data from: QTL mapping of volatile compound production in Saccharomyces cerevisiae during alcoholic fermentation

description: Background: The volatile metabolites produced by Saccharomyces cerevisiae
 during alcoholic fermentation, which are mainly esters, higher alcohols
 and organic acids, play a vital role in the quality and perception of
 fermented beverages, such as wine. Although the metabolic pathways and
 genes behind yeast fermentative aroma formation are well described, little
 is known about the genetic mechanisms underlying variations between
 strains in the production of these aroma compounds. To increase our
 knowledge about the links between genetic variation and volatile
 production, we performed quantitative trait locus (QTL) mapping using 130
 F2-meiotic segregants from two S. cerevisiae wine strains. The segregants
 were individually genotyped by next-generation sequencing and separately
 phenotyped during wine fermentation. Results: Using different QTL mapping
 strategies, we were able to identify 65 QTLs in the genome, including 55
 that influence the formation of 30 volatile secondary metabolites, 14 with
 an effect on sugar consumption and central carbon metabolite production,
 and 7 influencing fermentation parameters. For ethyl lactate, ethyl
 octanoate and propanol formation, we discovered 2 interacting QTLs each.
 Within 9 of the detected regions, we validated the contribution of 13
 genes in the observed phenotypic variation by reciprocal hemizygosity
 analysis. These genes are involved in nitrogen uptake and metabolism
 (AGP1, ALP1, ILV6, LEU9), central carbon metabolism (HXT3, MAE1), fatty
 acid synthesis (FAS1) and regulation (AGP2, IXR1, NRG1, RGS2, RGT1, SIR2)
 and explain variations in the production of characteristic sensorial
 esters (e.g., 2-phenylethyl acetate, 2-metyhlpropyl acetate and ethyl
 hexanoate), higher alcohols and fatty acids. Conclusions: The detection of
 QTLs and their 51 interactions emphasizes the complexity of yeast
 fermentative aroma formation. The validation of underlying allelic
 variants increases knowledge about genetic variation impacting metabolic
 pathways that lead to the synthesis of sensorial important compounds. As a
 result, this work lays the foundation for tailoring S. cerevisiae strains
 with optimized volatile metabolite production for fermented beverages and
 other biotechnological applications.
description: Microsatellite-treeMicrosatellite dataset, R script and tree of 445 strains indicating the phylogenic position of 4CAR1 and T73 used for QTL mapping. Read me text is included in the compressed archivePhenotypic data for QTL analysisDescription: comma-seperated values file containing the phenotype data of 130 evaluated segregant strains (Id).results4QTLanalysis.csvGenotypes of all_finalDescription: genotype file at R-QTL format, containing the identities of 3457 markers for 125 segregant strains (Id) that were used for the QTL mapping. These makers have a minim distance of 2kb between them. Identity "A" corresponds to nucleotide contributed by parent 4CAR1, identity "B" corresponds to nucleotide contributed by parent T73. First line contains the Id of each marker : “chromosome_coordinates”, line 2 indicates the chromosome, and line 3 indicates the coordinates in cm (coordinates / 3000)genotypesAll2000_final.csvSNPeffectDescription: comma-seperated values file listing all SNPs between the parent strains of the study, 4CAR1 and T73 with potential effect. The effects of SNPs on genes was predicted by SnpEff version 4.1.