Trabalzini Lorenza, Paffetti Alessandro, Scaloni Andrea, Talamo Fabio, Ferro Elisa, Coratza Grazietta, Bovalini Lucia, Lusini Paola, Martelli Paola, Santucci Annalisa
Dipartimento di Biologia Molecolare, Università degli Studi di Siena, via Fiorentina 1, 53100 Siena, Italy.
Biochem J. 2003 Feb 15;370(Pt 1):35-46. doi: 10.1042/BJ20020140.
We report a study on the adaptive response of a wild-type wine Saccharomyces cerevisiae strain, isolated from natural spontaneous grape must, to mild and progressive physiological stresses due to fermentation. We observed by two-dimensional electrophoresis how the yeast proteome changes during glucose exhaustion, before the cell enters its complete stationary phase. On the basis of their identification, the proteins representing the S. cerevisiae proteomic response to fermentation stresses were divided into three classes: repressed proteins, induced proteins and autoproteolysed proteins. In an overall view, the proteome adaptation of S. cerevisiae at the time of glucose exhaustion seems to be directed mainly against the effects of ethanol, causing both hyperosmolarity and oxidative responses. Stress-induced autoproteolysis is directed mainly towards specific isoforms of glycolytic enzymes. Through the use of a wild-type S. cerevisiae strain and PMSF, a specific inhibitor of vacuolar proteinase B, we could also distinguish the specific contributions of the vacuole and the proteasome to the autoproteolytic process.
我们报告了一项关于从天然自发葡萄汁中分离出的野生型酿酒酵母菌株对发酵引起的轻度渐进性生理应激的适应性反应的研究。我们通过二维电泳观察了在细胞进入完全静止期之前葡萄糖耗尽期间酵母蛋白质组的变化。根据蛋白质的鉴定结果，代表酿酒酵母对发酵应激的蛋白质组反应的蛋白质分为三类：受抑制蛋白质、诱导蛋白质和自蛋白水解蛋白质。总体来看，葡萄糖耗尽时酿酒酵母的蛋白质组适应性似乎主要针对乙醇的影响，乙醇会引发高渗和氧化反应。应激诱导的自蛋白水解主要针对糖酵解酶的特定同工型。通过使用野生型酿酒酵母菌株和液泡蛋白酶B的特异性抑制剂苯甲基磺酰氟（PMSF），我们还能够区分液泡和蛋白酶体对自蛋白水解过程的具体贡献。
