Genome-wide identification of Saccharomyces cerevisiae genes required for tolerance to acetic acid.
Genome-wide identification of Saccharomyces cerevisiae genes required for tolerance to acetic acid.
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DOI：
10.1186/1475-2859-9-79
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发表时间：
2010-10-25
影响因子：
6.4
通讯作者：
Sá-Correia I
中科院分区：
文献类型：
--
作者：
Mira NP;Palma M;Guerreiro JF;Sá-Correia I
醋酸是酿酒酵母酒精发酵的副产物。与高浓度乙醇和其他有毒代谢物一起，醋酸可能导致发酵停滞和乙醇产量降低。这种弱酸也存在于木质纤维素水解物中，这是工业生物技术中一种非常有趣的非原料底物。因此，更好地了解酿酒酵母对醋酸耐受的分子机制对于合理选择最佳发酵条件和设计更强大的工业菌株至关重要，这些菌株将用于酵母作为细胞工厂的探索过程中。本研究通过筛选EUROSCARF单倍体突变体对醋酸的敏感性表型（浓度在70-110 mM范围内，pH值为4.5），在全基因组范围内鉴定了具有醋酸保护作用的酵母基因。确定了大约650个醋酸耐受性决定因素。根据这些抗乙酸基因的生物学功能进行聚类，表明这些基因的富集涉及转录、内部pH稳态、碳水化合物代谢、细胞壁组装、线粒体、核糖体和液泡的生物发生，以及各种营养物质（特别是铁、钾、葡萄糖和氨基酸）的感知、信号传导和吸收。发现了生长培养基中钾含量与抗乙酸能力增强之间的相关性。Snf1p信号通路的激活，参与酵母对葡萄糖饥饿的反应，被证明发生在对醋酸胁迫的反应中，但没有证据支持醋酸诱导的葡萄糖摄取抑制。在这项研究中发现的650个醋酸耐受性决定因素中，约有490个与对这种弱酸的耐受性有关。这些都是新的候选基因，用于基因工程，以获得更强大的抗醋酸毒性酵母菌株。在这些基因中，有许多转录因子被证明是大部分基因的调节因子，这些基因被发现对醋酸具有保护作用，因此被认为是后续基因工程的有趣目标。研究发现，培养基中钾浓度的增加可以提高酵母对醋酸的最大耐受性表达，这与适当控制工业培养基的营养浓度可能是一种有趣的策略来克服这种弱酸对酵母细胞的有害影响的观点一致。
Acetic acid is a byproduct of Saccharomyces cerevisiae alcoholic fermentation. Together with high concentrations of ethanol and other toxic metabolites, acetic acid may contribute to fermentation arrest and reduced ethanol productivity. This weak acid is also a present in lignocellulosic hydrolysates, a highly interesting non-feedstock substrate in industrial biotechnology. Therefore, the better understanding of the molecular mechanisms underlying S. cerevisiae tolerance to acetic acid is essential for the rational selection of optimal fermentation conditions and the engineering of more robust industrial strains to be used in processes in which yeast is explored as cell factory. The yeast genes conferring protection against acetic acid were identified in this study at a genome-wide scale, based on the screening of the EUROSCARF haploid mutant collection for susceptibility phenotypes to this weak acid (concentrations in the range 70-110 mM, at pH 4.5). Approximately 650 determinants of tolerance to acetic acid were identified. Clustering of these acetic acid-resistance genes based on their biological function indicated an enrichment of genes involved in transcription, internal pH homeostasis, carbohydrate metabolism, cell wall assembly, biogenesis of mitochondria, ribosome and vacuole, and in the sensing, signalling and uptake of various nutrients in particular iron, potassium, glucose and amino acids. A correlation between increased resistance to acetic acid and the level of potassium in the growth medium was found. The activation of the Snf1p signalling pathway, involved in yeast response to glucose starvation, is demonstrated to occur in response to acetic acid stress but no evidence was obtained supporting the acetic acid-induced inhibition of glucose uptake. Approximately 490 of the 650 determinants of tolerance to acetic acid identified in this work are implicated, for the first time, in tolerance to this weak acid. These are novel candidate genes for genetic engineering to obtain more robust yeast strains against acetic acid toxicity. Among these genes there are number of transcription factors that are documented regulators of a large percentage of the genes found to exert protection against acetic acid thus being considered interesting targets for subsequent genetic engineering. The increase of potassium concentration in the growth medium was found to improve the expression of maximal tolerance to acetic acid, consistent with the idea that the adequate manipulation of nutrient concentration of industrial growth medium can be an interesting strategy to surpass the deleterious effects of this weak acid in yeast cells.
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影响因子：
2.8
作者：
Macpherson, N;Shabala, L;Davies, JM
通讯作者：
Davies, JM
影响因子：
12.3
作者：
Eide DJ;Clark S;Nair TM;Gehl M;Gribskov M;Guerinot ML;Harper JF
通讯作者：
Harper JF
影响因子：
56.9
作者：
Hillenmeyer, Maureen E.;Fung, Eula;Giaever, Guri
通讯作者：
Giaever, Guri
DOI：
10.1016/j.bbrc.2003.11.072
发表时间：
2003-12-26
影响因子：
3.1
作者：
Fernandes, AR;Durao, PJ;Sá-Correia, I
通讯作者：
Sá-Correia, I
影响因子：
3.2
作者：
Mira, Nuno P.;Lourenco, Artur B.;Sa-Correia, Isabel
通讯作者：
Sa-Correia, Isabel