Genomic analysis of commercial wine yeast strains

Humans have been consuming wines for more than 7,000 years. For most of this time, the fermentation was performed by strains of S. cerevisiae that naturally found their way into the fermenting must. However, most commercial wines are now produced by inoculation with pure yeast strains, ensuring consistent, reliable and reproducible fermentations and there are hundreds of yeast starter cultures that are now commercially available. In order to thoroughly investigate the genetic diversity that has been captured by over 50 years of commercial wine yeast development, whole genome sequencing has been performed on 212 strains of S. cerevisiae, including 119 commercial wine and brewing starter strains. Comparative genomic analysis has shown that, despite their large numbers, commercial strains, and wine strains in general, remain genetically similar, with high levels of apparent in-breeding. In addition, many commercial strains have near-identical counterparts, from multiple suppliers, suggesting that the limits of effective “industrial” variation within this group may me approaching saturation.

人类饮用葡萄酒的历史已有七千余年。在此绝大多数时期，发酵过程均由自然进入发酵醪液的酿酒酵母（Saccharomyces cerevisiae，简称S. cerevisiae）菌株完成。然而如今绝大多数商业葡萄酒均采用纯酵母菌株接种发酵，以确保发酵过程稳定、可靠且可重复，目前已有数百种商用酵母发酵剂菌种上市。为全面解析50余年商用葡萄酒酵母研发历程中所积累的遗传多样性，已对212株酿酒酵母菌株开展全基因组测序，其中包含119株商用葡萄酒与酿酒发酵剂菌株。比较基因组学分析结果显示，尽管商用菌株乃至整体葡萄酒菌株数量庞大，但它们在遗传层面仍高度相似，且表观近交程度极高。此外，多款商用菌株在不同供应商处均存在近乎完全一致的同源菌株，这表明该类菌株的有效"工业"变异范围或已接近饱和。