Evolutionary engineering in chemostat cultures for improved maltotriose fermentation kinetics in saccharomyces pastorianus lager brewing yeast
| Autor: | Frederico Magalhães, Jack T. Pronk, Anja Brickwedde, Marcel van den Broek, Niels G. A. Kuijpers, Jan-Maarten A. Geertman, Jean-Marc Daran, Brian Gibson |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2017 |
| Předmět: |
0301 basic medicine
Microbiology (medical) Sucrose lcsh:QR1-502 Chemostat Microbiology lcsh:Microbiology evolutionary engineering 03 medical and health sciences chemistry.chemical_compound Maltotriose Original Research chemostat biology business.industry ta1183 food and beverages maltotriose consumption rate Maltose Saccharomyces pastorianus biology.organism_classification Yeast 030104 developmental biology chemistry Biochemistry OA-Fund TU Delft brewing Maltotriose transport transport Brewing maltose business sacchromyces pastorianus |
| Zdroj: | Frontiers in Microbiology, Vol 8 (2017) Frontiers in Microbiology Brickwedde, A, van den Broek, M, Geertman, J-M A, Magalhães, F, Kuijpers, N G A, Gibson, B, Pronk, J T & Daran, J-M G 2017, ' Evolutionary engineering in chemostat cultures for improved maltotriose fermentation kinetics in saccharomyces pastorianus lager brewing yeast ', Frontiers in Microbiology, vol. 8, 1690 . https://doi.org/10.3389/fmicb.2017.01690 Frontiers in Microbiology, 8 |
| ISSN: | 1664-302X |
| Popis: | The lager brewing yeast Saccharomyces pastorianus, an interspecies hybrid of S. eubayanus and S. cerevisiae, ferments maltotriose, maltose, sucrose, glucose and fructose in wort to ethanol and carbon dioxide. Complete and timely conversion ("attenuation") of maltotriose by industrial S. pastorianus strains is a key requirement for process intensification. This study explores a new evolutionary engineering strategy for improving maltotriose fermentation kinetics. Prolonged carbon-limited, anaerobic chemostat cultivation of the reference strain S. pastorianus CBS1483 on a maltotriose-enriched sugar mixture was used to select for spontaneous mutants with improved affinity for maltotriose. Evolved populations exhibited an up to 5-fold lower residual maltotriose concentration and a higher ethanol concentration than the parental strain. Uptake studies with 14C-labeled sugars revealed an up to 4.75-fold higher transport capacity for maltotriose in evolved strains. In laboratory batch cultures on wort, evolved strains showed improved attenuation and higher ethanol concentrations. These improvements were also observed in pilot fermentations at 1,000-L scale with high-gravity wort. Although the evolved strain exhibited multiple chromosomal copy number changes, analysis of beer made from pilot fermentations showed no negative effects on flavor compound profiles. These results demonstrate the potential of evolutionary engineering for strain improvement of hybrid, alloploid brewing strains. |
| Databáze: | OpenAIRE |
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