OBJECTIVES: To improve the storage stability and reusability of various yeast strains and species by immobilization in polyvinyl alcohol (PVA) hydrogel particles. RESULTS: Debaryomyces hansenii, Pichia sorbitophila, Saccharomyces cerevisiae, Yarrowia lipolytica, and Zygosaccharomyces rouxii were immobilized in PVA particles using LentiKats technology and stored in sterile water at 4 °C. The immobilization improved the survival of all species; however, the highest storage stability was achieved for S. cerevisiae and Y. lipolytica which survived more than 1 year, in contrast to free cells that survived for only 3 months. Tests of the reusability of immobilized recombinant laccase-secreting S. cerevisiae revealed that the cells were suitable for repetitive use (55 cycles during 15 months) even after storage in water at 4 °C for 9 months. A suitable method for killing immobilized laccase-secreting cells without affecting the produced enzyme activity was also developed. CONCLUSIONS: The immobilization of yeasts in PVA hydrogel enables long-term, cheap storage with very good cell viability and productivity, thus becoming a promising approach for industrial applications.
- MeSH
- biotechnologie MeSH
- buněčné kultury MeSH
- imobilizované buňky * cytologie enzymologie metabolismus MeSH
- lakasa chemie metabolismus MeSH
- mikrobiální viabilita MeSH
- ochrana biologická metody MeSH
- opakované použití vybavení MeSH
- polyvinylalkohol chemie MeSH
- rekombinantní proteiny chemie metabolismus MeSH
- Saccharomyces cerevisiae * cytologie enzymologie metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
Saccharomyces species, which are mostly used in the food and beverage industries, are known to differ in their fermentation efficiency and tolerance of adverse fermentation conditions. However, the basis of their difference has not been fully elucidated, although their genomes have been sequenced and analyzed. Five strains of four Saccharomyces species (S. cerevisiae, S. kudriavzevii, S. bayanus, and S. paradoxus), when grown in parallel in laboratory conditions, exhibit very similar basic physiological parameters such as membrane potential, intracellular pH, and the degree to which they are able to quickly activate their Pma1 H+-ATPase upon glucose addition. On the other hand, they differ in their ability to proliferate in media with a very low concentration of potassium, in their osmotolerance and tolerance to toxic cations and cationic drugs in a growth-medium specific manner, and in their capacity to survive anhydrobiosis. Overall, S. cerevisiae (T73 more than FL100) and S. paradoxus are the most robust, and S. kudriavzevii the most sensitive species. Our results suggest that the difference in stress survival is based on their ability to quickly accommodate their cell size and metabolism to changing environmental conditions and to adjust their portfolio of available detoxifying transporters.
Dekkera bruxellensis is important for lambic beer fermentation but is considered a spoilage yeast in wine fermentation. We compared two D. bruxellensis strains isolated from wine and found that they differ in some basic properties, including osmotolerance. The genomes of both strains contain two highly similar copies of genes encoding putative glycerol-proton symporters from the STL family that are important for yeast osmotolerance. Cloning of the two DbSTL genes and their expression in suitable osmosensitive Saccharomyces cerevisiae mutants revealed that both identified genes encode functional glycerol uptake systems, but only DbStl2 has the capacity to improve the osmotolerance of S. cerevisiae cells.
- MeSH
- Dekkera genetika izolace a purifikace metabolismus fyziologie MeSH
- druhová specificita MeSH
- fungální proteiny genetika metabolismus MeSH
- genom bakteriální genetika MeSH
- glycerol metabolismus MeSH
- osmoregulace genetika MeSH
- protony MeSH
- rekombinantní proteiny genetika metabolismus MeSH
- Saccharomyces cerevisiae genetika MeSH
- symportéry genetika metabolismus MeSH
- testy genetické komplementace MeSH
- víno mikrobiologie MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- srovnávací studie MeSH
Osmotolerance is the ability to grow in an environment with a high osmotic pressure. In this study we compared the physiological parameters and tolerance to osmotic and non-osmotic stresses of three osmotolerant yeast species, Debaryomyces hansenii, Pichia farinosa (sorbitophila) and Zygosaccharomyces rouxii, with those of wild-type Saccharomyces cerevisiae. Although the osmotolerant species did not differ significantly in their basic parameters, such as cell size or growth capacity, they had different abilities to survive anhydrobiosis, potassium limitation or the presence of toxic cationic drugs. When their osmotolerance was compared, the results revealed that some of the species isolated as sugar/polyol-tolerant (e.g. P. farinosa) are also highly tolerant to salts and, vice versa, some strains isolated from an environment with high concentration of salt (e.g. Z. rouxii ATCC 42981) tolerate high concentrations of sugars. None of the tested strains and species was osmophilic. Taken together, our results showed that P. farinosa (sorbitophila) is the most robust species when coping with various stresses, while Z. rouxii CBS 732, although osmotolerant in general, is not specifically salt-tolerant and is quite sensitive to most of the tested stress conditions.
- MeSH
- fyziologický stres * MeSH
- metabolismus sacharidů MeSH
- mikrobiální viabilita účinky léků MeSH
- osmotický tlak * MeSH
- polymery metabolismus MeSH
- Saccharomycetales účinky léků růst a vývoj fyziologie MeSH
- soli metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- srovnávací studie MeSH
