PDF(Pubmed)
Abstract：
The widespread use of copper-based pesticides in winemaking can affect wine fermentation. Therefore, it is crucial to assess the resistance levels of Saccharomyces cerevisiae wine strains in enological growth conditions. In the context of winemaking, grape juice is a complex environment capable of chelating copper and is characterized by a distinctly acidic pH. In this work, the effects of copper concentration on the growth of 10 S. cerevisiae strains, isolated from an enological environment, and one commercial starter were tested in YNB minimal medium and synthetic must, mimicking enological conditions. In minimal medium, resistance to copper varied among yeasts (50-600 μM), revealing the presence of three resistance levels (high, intermediate, and low). Representative strains of the three groups were tested at a pH range from 5.2 to 3.0 at the copper concentration that showed a 20-25 % growth reduction. At pH range 5.2-4.5, a growth reduction was observed, while, conversely, a strain-specific recovery was observed at pH range 3.2-3.0. In synthetic must, the strains showed higher copper resistance levels than in minimal medium (50-4000 μM). In both synthetic must and minimal medium, a significant logarithmic correlation was found between copper resistance and CUP1 gene copy number. The copy number tended to better explain resistance in minimal medium compared to synthetic must. The results shed light on the role of CUP1 copy number within an enological environment.
摘要：
铜基农药在酿酒中的广泛使用会影响葡萄酒的发酵。因此,评估酿酒酵母葡萄酒菌株在植物生长条件下的抗性水平至关重要。在酿酒的背景下，葡萄汁是一种能够螯合铜的复杂环境，其特征是具有明显的酸性pH值。在这项工作中,铜浓度对10株酿酒酵母生长的影响,与环境隔离，并在YNB最低培养基和合成必须中测试了一种商业起动器，模仿环境条件。在最低限度的培养基中，对铜的抗性因酵母而异（50-600μM），揭示存在三个阻力水平(高，中间,和低）。三组的代表性菌株在5.2至3.0的pH范围下在显示20-25%生长减少的铜浓度下进行测试。在pH范围5.2-4.5，观察到生长减少，while,相反,在pH范围3.2-3.0时观察到菌株特异性恢复。在合成必须中，菌株显示出比基本培养基（50-4000μM）更高的铜抗性水平。在合成必须和最低限度介质中，铜抗性与CUP1基因拷贝数之间存在显著的对数相关性.与合成必须相比，拷贝数倾向于更好地解释基本培养基中的抗性。结果揭示了CUP1拷贝数在环境中的作用。
