Adamczyk Jagoda, Deregowska Anna, Potocki Leszek, Kuna Ewelina, Kaplan Jakub, Pabian Sylwia, Kwiatkowska Aleksandra, Lewinska Anna, Wnuk Maciej
Department of Genetics, University of Rzeszow, Rejtana 16C, 35-959, Rzeszow, Poland.
Postgraduate School of Molecular Medicine, Medical University of Warsaw, Warsaw, Poland.
Arch Microbiol. 2016 Sep;198(7):715-23. doi: 10.1007/s00203-016-1258-9. Epub 2016 Jun 21.
Distillery yeasts are poorly characterized physiological group among the Saccharomyces sensu stricto complex. As industrial yeasts are under constant environmental stress during fermentation processes and the nucleolus is a stress sensor, in the present study, nucleolus-related parameters were evaluated in 22 commercially available distillery yeast strains. Distillery yeasts were found to be a heterogeneous group with a variable content and length of rDNA and degree of nucleolus fragmentation. The levels of rDNA were negatively correlated with Nop1 (r = -0.59, p = 0.0038). Moreover, the protein levels of Sir transcriptional silencing complex and longevity regulators, namely Sir1, Sir2, Sir3 and Fob1, were studied and negative correlations between Sir2 and Nop1 (r = -0.45, p = 0.0332), and between Sir2 and Fob1 (r = -0.49, p = 0.0211) were revealed. In general, S. paradoxus group of distillery yeasts with higher rDNA pools and Sir2 level than S. bayanus group was found to be more tolerant to fermentation-associated stress stimuli, namely mild cold/heat stresses and KCl treatment. We postulate that rDNA state may be considered as a novel factor that may modulate a biotechnological process.
在狭义酿酒酵母复合体中，酿酒酵母是生理特征 poorly characterized 的一个群体。由于工业酵母在发酵过程中持续处于环境压力之下，且核仁是一种压力传感器，因此在本研究中，我们评估了 22 种市售酿酒酵母菌株中与核仁相关的参数。结果发现，酿酒酵母是一个异质群体，其核糖体 DNA（rDNA）的含量和长度以及核仁碎片化程度各不相同。rDNA 的水平与 Nop1 呈负相关（r = -0.59，p = 0.0038）。此外，我们还研究了 Sir 转录沉默复合体和寿命调节因子（即 Sir1、Sir2、Sir3 和 Fob1）的蛋白质水平，结果显示 Sir2 与 Nop1 之间（r = -0.45，p = 0.0332）以及 Sir2 与 Fob1 之间（r = -0.49，p = 0.0211）存在负相关。总体而言，与巴氏酵母组相比，rDNA 库和 Sir2 水平较高的酿酒酵母中的奇异酵母组被发现对与发酵相关的应激刺激（即轻度冷/热应激和 KCl 处理）具有更强的耐受性。我们推测，rDNA 状态可能被视为一种可调节生物技术过程的新因素。
