Jiménez-Martí E, Zuzuarregui A, Ridaura I, Lozano N, del Olmo M
Departament de Bioquímica i Biologia Molecular, Universitat de València, Burjassot, Valencia, Spain.
Int J Food Microbiol. 2009 Mar 31;130(2):122-30. doi: 10.1016/j.ijfoodmicro.2009.01.017. Epub 2009 Jan 24.
Throughout wine production yeast cells are affected by a plethora of stress conditions that compromise their ability to carry out the whole process. In recent years important knowledge about the mechanisms involved in stress response in both laboratory and wine yeast strains has been obtained. Several studies have indicated that a correlation exists between stress resistance, expression of stress response genes and fermentative behaviour. In this work we introduce several genetic manipulations in two genes induced by several stress conditions: HSP26 (which encodes a heat shock protein) and YHR087W (encoding a protein of unknown function) in two different wine yeasts, ICV16 and ICV27. These manipulations include expression in multicopy and centromeric plasmids, and substitution of the promoter in one of the genomic copies of these genes for that of the SPI1 gene, encoding for a cell wall protein of unknown function, or the PGK1 gene, which encodes the phosphoglycerate kinase glycolytic enzyme. Our results indicate that some of these modifications result in strains with higher expression of these genes, better resistance to certain stress conditions, and even improved fermentative behaviour. The modifications of the YHR087W gene are particularly interesting, and suggest an important role of this gene in the vinification process.
在整个葡萄酒生产过程中，酵母细胞会受到大量应激条件的影响，这些应激条件会损害它们完成整个过程的能力。近年来，已经获得了关于实验室酵母菌株和葡萄酒酵母菌株应激反应相关机制的重要知识。多项研究表明，抗逆性、应激反应基因的表达与发酵行为之间存在相关性。在这项工作中，我们对两种不同的葡萄酒酵母ICV16和ICV27中的两个受多种应激条件诱导的基因进行了几种基因操作：HSP26（编码一种热休克蛋白）和YHR087W（编码一种功能未知的蛋白质）。这些操作包括在多拷贝和着丝粒质粒中表达，以及将这些基因的一个基因组拷贝中的启动子替换为SPI1基因（编码一种功能未知的细胞壁蛋白）或PGK1基因（编码磷酸甘油酸激酶糖酵解酶）的启动子。我们的结果表明，其中一些修饰导致这些基因表达更高的菌株，对某些应激条件具有更好的抗性，甚至改善了发酵行为。YHR087W基因的修饰特别有趣，并表明该基因在葡萄酒酿造过程中具有重要作用。
