A small number (10 to 20) of yeast species cause major spoilage in foods. Spoilage yeasts of soft drinks are resistant to preservatives like sorbic acid, and they are highly fermentative, generating large amounts of carbon dioxide gas. Conversely, many yeast species derive energy from respiration only, and most of these are sorbic acid sensitive and so prevented from causing spoilage. This led us to hypothesize that sorbic acid may specifically inhibit respiration. Tests with respirofermentative yeasts showed that sorbic acid was more inhibitory to both Saccharomyces cerevisiae and Zygosaccharomyces bailii during respiration (of glycerol) than during fermentation (of glucose). The respiration-only species Rhodotorula glutinis was equally sensitive when growing on either carbon source, suggesting that ability to ferment glucose specifically enables sorbic acid-resistant growth. Sorbic acid inhibited the respiration process more strongly than fermentation. We present a data set supporting a correlation between the level of fermentation and sorbic acid resistance across 191 yeast species. Other weak acids, C₂ to C₈, inhibited respiration in accordance with their partition coefficients, suggesting that effects on mitochondrial respiration were related to membrane localization rather than cytosolic acidification. Supporting this, we present evidence that sorbic acid causes production of reactive oxygen species, the formation of petite (mitochondrion-defective) cells, and Fe-S cluster defects. This work rationalizes why yeasts that can grow in sorbic acid-preserved foods tend to be fermentative in nature. This may inform more-targeted approaches for tackling these spoilage organisms, particularly as the industry migrates to lower-sugar drinks, which could favor respiration over fermentation in many spoilage yeasts.

中文翻译：

---

防腐性山梨酸靶向呼吸作用，解释了发酵腐败酵母菌的抗性。

少数酵母菌（10至20种）会严重破坏食品。软饮料的腐败酵母对山梨酸等防腐剂具有抵抗力，并且具有很高的发酵能力，会产生大量二氧化碳气体。相反，许多酵母菌仅从呼吸中获取能量，其中大多数对山梨酸敏感，因此可以防止腐败。这使我们假设山梨酸可能特异性抑制呼吸。呼吸发酵酵母的测试表明，在呼吸过程中（甘油），山梨酸对酿酒酵母和百日酵母的抑制作用要比发酵过程中（葡萄糖）的抑制作用更大。仅呼吸的物种Rhodotorula glutinis在任何一种碳源上生长时同样敏感，表明发酵葡萄糖的能力可以特异性地使山梨酸具有抗性。山梨酸比发酵更能抑制呼吸过程。我们提出了一个数据集，它支持191种酵母菌的发酵水平与山梨酸抗性之间的相关性。其他弱酸，C ₂至C ₈，根据其分配系数，抑制了呼吸作用，提示对线粒体呼吸作用的影响与膜定位有关，而不与胞质酸化有关。支持这一点，我们提供证据表明，山梨酸会引起活性氧的产生，娇小（线粒体缺陷型）细胞的形成以及Fe-S团簇缺陷。这项工作合理化了为什么可以在保存有山梨酸的食物中生长的酵母在本质上倾向于发酵的原因。这可能为解决这些变质微生物提供了更具针对性的方法，尤其是当该行业向低糖饮料迁移时，在许多变质酵母中，它们可能比发酵更有利于呼吸。