Laboratory evolution of copper tolerant yeast strains.
Laboratory evolution of copper tolerant yeast strains.
复制标题
DOI：
10.1186/1475-2859-11-1
复制
发表时间：
2012-01-03
影响因子：
6.4
通讯作者：
Lotti M
中科院分区：
文献类型：
--
作者：
Adamo GM;Brocca S;Passolunghi S;Salvato B;Lotti M
酵母菌株赋予鲁棒性对铜和/或丰富的细胞内铜可能会发现在生物技术过程中的应用，除其他外，在功能性食品的生产。此外，它们可以有助于与铜代谢障碍相关的人类疾病的研究。在这项研究中，我们调查的分子和生理因素，赋予耐铜的面包酵母菌株。我们的特点引起的影响，在自然菌株的念珠菌humilis和酿酒酵母暴露于铜的培养液。我们观察到，虽然酵母细胞的生长在低浓度的铜已经被抑制，C。humilis对1g· L-1CuSO 4具有较强的耐受性。这种耐药菌株积累了超过7毫克的铜每克生物量和逃避严重的氧化应激由于高组成水平的超氧化物歧化酶和过氧化氢酶。然后，这两种酵母被“进化”以获得能够在高铜培养基中增殖的超抗性细胞。而在S.在酿酒酵母中，抗氧化酶的增加抑制了对Cu的鲁棒性的进化，而在进化的超耐药念珠菌细胞中，这些相同的活性降低。我们还在一些细节的铜结合蛋白的配置文件的变化，这似乎是修改的进化，但再次，在两种酵母菌以不同的方式。经过进化，酵母菌和假丝酵母菌在2.5g· L-1CuSO 4浓度下都能增殖并积累大量的胞内铜。酵母菌在其稳健性不同的比较，允许突出自然和后天铜耐受性的生理和分子决定因素。我们观察到，不同的机制有助于赋予金属耐受性：控制铜的吸收，参与氧化应激反应的酶的水平的变化和铜结合蛋白质组的变化。然而，铜在不同背景的酵母中引起不同的生理和分子反应。
Yeast strains endowed with robustness towards copper and/or enriched in intracellular Cu might find application in biotechnology processes, among others in the production of functional foods. Moreover, they can contribute to the study of human diseases related to impairments of copper metabolism. In this study, we investigated the molecular and physiological factors that confer copper tolerance to strains of baker's yeasts. We characterized the effects elicited in natural strains of Candida humilis and Saccharomyces cerevisiae by the exposure to copper in the culture broth. We observed that, whereas the growth of Saccharomyces cells was inhibited already at low Cu concentration, C. humilis was naturally robust and tolerated up to 1 g · L-1 CuSO4 in the medium. This resistant strain accumulated over 7 mg of Cu per gram of biomass and escaped severe oxidative stress thanks to high constitutive levels of superoxide dismutase and catalase. Both yeasts were then "evolved" to obtain hyper-resistant cells able to proliferate in high copper medium. While in S. cerevisiae the evolution of robustness towards Cu was paralleled by the increase of antioxidative enzymes, these same activities decreased in evolved hyper-resistant Candida cells. We also characterized in some detail changes in the profile of copper binding proteins, that appeared to be modified by evolution but, again, in a different way in the two yeasts. Following evolution, both Candida and Saccharomyces cells were able to proliferate up to 2.5 g · L-1 CuSO4 and to accumulate high amounts of intracellular copper. The comparison of yeasts differing in their robustness, allowed highlighting physiological and molecular determinants of natural and acquired copper tolerance. We observed that different mechanisms contribute to confer metal tolerance: the control of copper uptake, changes in the levels of enzymes involved in oxidative stress response and changes in the copper-binding proteome. However, copper elicits different physiological and molecular reactions in yeasts with different backgrounds.
登录
查看更多内容
影响因子：
6.4
作者：
Gómez-Pastor R;Pérez-Torrado R;Cabiscol E;Ros J;Matallana E
通讯作者：
Matallana E
影响因子：
4.1
作者：
Cakar, Z. Petek;Alkim, Ceren;Francois, Jean M.
通讯作者：
Francois, Jean M.
影响因子：
4.5
作者：
Contreras, Loretto;Moenne, Alejandra;Correa, Juan A.
通讯作者：
Correa, Juan A.
影响因子：
4.4
作者：
Guimaraes, Pedro M. R.;Francois, Jean;Domingues, Lucilia
通讯作者：
Domingues, Lucilia
影响因子：
3.2
作者：
Abbott, Derek A.;Knijnenburg, Theo A.;van Maris, Antonius J. A.
通讯作者：
van Maris, Antonius J. A.