Regulation involved in difference in nitrogen requirements of Saccharomyces cerevisiae wine yeasts in alcoholic fermentation. Saccharomyces cerevisiae

The objective of this work is to identify, in enological condition, differences in transcriptomic regulation that may explain the differences in strains fermentation properties. For this, we compared the global expression patterns of 8 Saccharomyces cerevisiae strains with different nitrogen requirement (L2868, 4CAR1, Fermiflor, Zymasil, MTF1782, 7013, K1M, EC1118). The transcriptome was analyzed on cells fermenting in a nitrogen limited medium containing 100mg.l-1 assimilable nitrogen (SM100) and harvested at stationary phase (45g/L of CO2 produced and corresponding to 6% ethanol). At this stage the strains exhibited differences in fermentation rates. Moreover, the transcriptome was shown to be rather stable at this stage since growth was stopped for all cells and nutrients have been depleted (Rossignol et al. 2003). Overall design: Eight strains with different nitrogen requirement were analyzed (L2868, 4CAR1, Fermiflor, Zymasil, MTF1782, 7013, K1M, EC1118). This analysis includes two biological replicates for each strain.

本研究旨在酿酒发酵条件下，解析可阐释酿酒酵母菌株发酵特性差异的转录调控差异。为此，我们选取8株氮需求特性存在差异的酿酒酵母（Saccharomyces cerevisiae）菌株（L2868、4CAR1、Fermiflor、Zymasil、MTF1782、7013、K1M、EC1118），对其全局基因表达谱开展比较分析。
实验中，所有菌株均在含100mg·L⁻¹可同化氮的限氮培养基（SM100）中进行发酵，于稳定期（发酵产生45g/L二氧化碳，对应乙醇浓度6%）收集菌体进行转录组分析。该阶段各菌株的发酵速率已呈现显著差异。此外，已有研究证实（Rossignol等，2003），此阶段所有菌体均停止生长且营养物质已耗尽，因此转录组水平相对稳定。
实验设计：本研究共分析8株氮需求特性存在差异的酿酒酵母菌株，每株菌株设置2次生物学重复。