Laboratory evolution of copper tolerant yeast strains
<p>Abstract</p> <p>Background</p> <p>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 stud...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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BMC
2012-01-01
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| Series: | Microbial Cell Factories |
| Subjects: | |
| Online Access: | http://www.microbialcellfactories.com/content/11/1/1 |
| _version_ | 1818790055504773120 |
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| author | Adamo Giusy Brocca Stefania Passolunghi Simone Salvato Benedetto Lotti Marina |
| author_facet | Adamo Giusy Brocca Stefania Passolunghi Simone Salvato Benedetto Lotti Marina |
| author_sort | Adamo Giusy |
| collection | DOAJ |
| description | <p>Abstract</p> <p>Background</p> <p>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.</p> <p>Results</p> <p>We characterized the effects elicited in natural strains of <it>Candida humilis </it>and <it>Saccharomyces cerevisiae </it>by the exposure to copper in the culture broth. We observed that, whereas the growth of <it>Saccharomyces </it>cells was inhibited already at low Cu concentration, <it>C. humilis </it>was naturally robust and tolerated up to 1 g · L<sup>-1 </sup>CuSO<sub>4 </sub>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 <it>S. cerevisiae </it>the evolution of robustness towards Cu was paralleled by the increase of antioxidative enzymes, these same activities decreased in evolved hyper-resistant <it>Candida </it>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.</p> <p>Conclusions</p> <p>Following evolution, both <it>Candida </it>and <it>Saccharomyces </it>cells were able to proliferate up to 2.5 g · L<sup>-1 </sup>CuSO<sub>4 </sub>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.</p> |
| first_indexed | 2024-12-18T14:49:22Z |
| format | Article |
| id | doaj.art-f3da72d1b0a0418393b0d69a2761289f |
| institution | Directory Open Access Journal |
| issn | 1475-2859 |
| language | English |
| last_indexed | 2024-12-18T14:49:22Z |
| publishDate | 2012-01-01 |
| publisher | BMC |
| record_format | Article |
| series | Microbial Cell Factories |
| spelling | doaj.art-f3da72d1b0a0418393b0d69a2761289f2022-12-21T21:04:13ZengBMCMicrobial Cell Factories1475-28592012-01-01111110.1186/1475-2859-11-1Laboratory evolution of copper tolerant yeast strainsAdamo GiusyBrocca StefaniaPassolunghi SimoneSalvato BenedettoLotti Marina<p>Abstract</p> <p>Background</p> <p>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.</p> <p>Results</p> <p>We characterized the effects elicited in natural strains of <it>Candida humilis </it>and <it>Saccharomyces cerevisiae </it>by the exposure to copper in the culture broth. We observed that, whereas the growth of <it>Saccharomyces </it>cells was inhibited already at low Cu concentration, <it>C. humilis </it>was naturally robust and tolerated up to 1 g · L<sup>-1 </sup>CuSO<sub>4 </sub>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 <it>S. cerevisiae </it>the evolution of robustness towards Cu was paralleled by the increase of antioxidative enzymes, these same activities decreased in evolved hyper-resistant <it>Candida </it>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.</p> <p>Conclusions</p> <p>Following evolution, both <it>Candida </it>and <it>Saccharomyces </it>cells were able to proliferate up to 2.5 g · L<sup>-1 </sup>CuSO<sub>4 </sub>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.</p>http://www.microbialcellfactories.com/content/11/1/1yeastcopperadaptationevolutionary engineeringoxidative stress responsemicronutrients |
| spellingShingle | Adamo Giusy Brocca Stefania Passolunghi Simone Salvato Benedetto Lotti Marina Laboratory evolution of copper tolerant yeast strains Microbial Cell Factories yeast copper adaptation evolutionary engineering oxidative stress response micronutrients |
| title | Laboratory evolution of copper tolerant yeast strains |
| title_full | Laboratory evolution of copper tolerant yeast strains |
| title_fullStr | Laboratory evolution of copper tolerant yeast strains |
| title_full_unstemmed | Laboratory evolution of copper tolerant yeast strains |
| title_short | Laboratory evolution of copper tolerant yeast strains |
| title_sort | laboratory evolution of copper tolerant yeast strains |
| topic | yeast copper adaptation evolutionary engineering oxidative stress response micronutrients |
| url | http://www.microbialcellfactories.com/content/11/1/1 |
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