随着消费者口味越来越多样化，苦味型啤酒等特色啤酒逐步受到大众青睐。申请人前期研究证实，在高浓度啤酒花苦味酸（异α-酸）作用下酵母逐渐进入活的不可培养（VBNC）状态，从而解释为何高苦味啤酒发酵后期酵母活力会显著下降。目前关于VBNC研究多集中于细菌，对酵母等真核生物的报道还相当匮乏。因此，亟需深入解析酵母应激形成VBNC状态的分子机理。本课题拟采用不同浓度异α-酸诱导啤酒酵母进入VBNC状态，比较状态转变过程的细胞生理及代谢特性变化，以明确VBNC酵母的形成规律；基于RNA测序，从转录组水平分析不同状态酵母的基因表达谱差异；运用生物信息学对差异基因进行结构分析和功能预测，定位调控VBNC形成的关键功能因子；利用实时荧光定量PCR和基因敲除技术对调控基因进行功能验证。研究结果将为揭示苦味酸诱导酵母VBNC状态产生的内在机制奠定理论基础，为解决高苦味啤酒发酵时酵母活力减弱的问题提供新思路。

With the increasing variety of consumer tastes, the special beers, including hoppy beers, becomes more and more popular. Our previous study found that yeast cells can gradually form the VBNC state in the presence of high concentration of hop bitter acids, which may lead to a significant decrease in yeast activity in the later stage of fermentation. So far, the VBNC state has been extensively studied in bacteria, but the researches on the VBNC yeast are still scarce. Therefore, it is necessary to study the induction and molecular mechanism of yeast in VBNC state. In this project, firstly in order to obtain the regulation of the formation of VBNC yeast cells, the different concentrations of iso-α-acid are used to treat yeast cells, and the difference of cell physiological and metabolic characteristics at different stages of state transformation was compared. Secondly, based on RNA sequencing the changes of gene expression profiles between the normal cells and VBNC cells of beer yeast are observed at the transcriptome level. Thirdly, the structural analysis and functional prediction of differential genes are carried out by bioinformatics. After the key functional genes are identified, the study is attempting to further determine their function using the gene knock out technique. Finally the genes and their regulation mechanism involved in the induction of VBNC yeast by hop bitter acids will be revealed. This work is expected to provide a theoretical basis for further development of the formation mechanism of VBNC state in yeast, and propose new solutions for solving the problem of insufficient yeast activity during fermentation of hoppy beers.