Spreading of wine yeast in the environment: monitoring the occurrence of sexual and asexual DNA transfers between yeast strains
Bauer, F F
University of Stellenbosch. Faculty of AgriSciences. Institute for Wine Biotechnology
Wolfaardt, G M
Bester, M C
Swiegers, J H
Van Dyk, D
Stidwell, T G
All biotechnological processes will be relying more and more on genetically modified organisms to improve industrial processes and to create improved or new products.
In the wine industry, the use of genetically improved yeast strains will become a reality in the near future. The approval of these strains by regulatory authorities and by consumers will depend on the scientific assessment of potential risks. This project proposes to study risks most commonly considered in approval processes, in particular the possible occurrence of the transfer of genetic material between different organisms.
This project is a logical extension of the successfully completed Winetech project on the spreading of commercial wine yeast in the vineyard, which indicated that commercial wine yeast strains appear to be unable to colonise vineyards or other natural habitats. The risk associated with the spreading of specific wine yeast strains, whether genetically modified or not, therefore appears to be low. However, the study did not investigate the possible occurrence of the transfer of DNA between different strains of the same species or between different species. In the case of genetically modified yeast strains, horizontal (i.e. non-sexual transfer between strains or species) or sexual DNA transfers, if they occur, would present a means of spreading genetic information without requiring the dissemination of the original, industrial host strain. The project will follow the possible spreading of specific, genetically modified fragments of DNA between different strains in conditions that theoretically should facilitate the occurrence of such transfers. Should such events be recorded, the project will investigate the molecular nature of the transfer.
Bauer, F F, Domingo, J L, Govender, P, Gupthar, A S and Pretorius, I S. 2000. Development of wine yeast strains with improved flocculation properties. Paper presented at the 2nd International Congress of the South African Society for Enology and Viticulture. 8-10 November, Cape Town, South Africa.
Verstrepen, K, Bauer, F F, Michiels, G, Derdelinckx, G, Delvaux, F and Pretorius, I S. 2000. Controlled expression of FLO1 in Saccharomyces cerevisiae. Paper presented at the 34th European Brewery Convention Congress. 26-30 May 2013, Luxembourg, Germany.
Pretorius, I S, Van der Westhuizen, T J, Augustyn, O P H. 1999. Yeast biodiversity in vineyards and wineries and its importance to the South African wine industry – a review, South African Journal of Enology and Viticulture, v. 20 (2) (p. 61-74)
Khan, W, Augustyn, O P H, Van der Westhuizen, T J, Lambrechts, M G, Pretorius, I S. 2000. Geographic distribution and evaluation of Saccharomyces cerevisiae strains isolated from vineyards in the warmer, inland regions of the Western Cape in South Africa, South African Journal of Enology and Viticulture, v. 21 (1) (p. 17-31)