Abstract

The aim of this study was to obtain new distilling strains of Saccharomyces cerevisiae with increased resistance to acetic acid, and, at the same time, characterized by high ethanol production. The first stage of the research focused on the construction of a parental strains library (4 strains) by carrying out a chemical mutagenesis using ethyl methanesulfonate. As a result, several dozen mutants were obtained, which subsequently were subjected to screening for the fermentation activity and resistance to acetic acid at the concentration of 0.05–0.2% vol/vol. After a total of two rounds of genome shuffling of mutants obtained from a pool of the parental library, 50 fusants were obtained. On the basis of rapid fermentation tests, the quality of the newly obtained strains was assessed. The volumetric ethanol productivity was used as a standard for the fermentation activity of the obtained fusants. In order to confirm the genetic changes expected a genetic analysis by PCR using ISSR primers was performed. This analysis shows that changes within the genome are visible in the case of newly developed strain. This improved strain was characterized by a 60% higher ethanol productivity (120 g/L) compared to the parental strain.

中文翻译：

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新型基因组改组提高酿酒酵母耐乙酸性

摘要

这项研究的目的是获得酿酒酵母的新蒸馏菌株。具有更高的耐乙酸性，同时具有高乙醇产量的特点。研究的第一阶段集中在通过使用甲磺酸乙酯进行化学诱变来构建亲本菌株文库（4个菌株）。结果，获得了几十个突变体，随后将其筛选以0.05-0.2％vol / vol的浓度筛选发酵活性和对乙酸的抗性。在从亲本文库库中获得的突变体总共进行了两轮基因组改组后，获得了50种融合剂。在快速发酵测试的基础上，评估了新获得菌株的质量。乙醇的体积生产率用作所获得的融合剂的发酵活性的标准。为了确认预期的遗传变化，使用ISSR引物通过PCR进行了遗传分析。该分析表明，在新近开发的菌株中，基因组内的变化是可见的。与亲代菌株相比，这种改良的菌株的特征在于乙醇生产率（120 g / L）提高了60％。