Mira, Nuno Gonçalo PereiraBarata, Margarida, 1958-Peixoto, João Miguel Condessa2024-11-2520242024http://hdl.handle.net/10400.5/95615Tese de mestrado, Microbiologia Aplicada , 2024, Universidade de Lisboa, Faculdade de CiênciasIn recent decades there has been an increase in studying non-Saccharomyces strains as co-adjuvants in winemaking due to their ability to synthesize aromatic molecules that are not typically produced by Saccharomyces cerevisiae enriching the aromatic profile of the wines obtained. Some non-Saccharomyces yeast species (e.g. Saturnispora diversa, the species at the center of this thesis) also show some biocontrol potential, that is, the ability to inhibit growth of undesirable contaminating species. In this thesis we focused as a target spoilage species the yeasts Saccharomycodes ludwigii and Zygosaccharomyces bailii, both linked to the degradation of wine quality by producing undesirable characteristics, causing cloudiness, among other deleterious effects. A first main goal of this work was to explore the biological information coming from the genome sequencing of a Saturnispora diversa strain isolated by the IST laboratory. For that, a comparative proteomic analysis between the predicted ORFeome of S. diversa and those predicted by other yeasts was undertaken, identifying in 188 proteins specific to S. diversa. The ORFeome predicted for the species Saturnispora saitoi (closely related to S. diversa) was also herein established for the first time and used in the undertaken comparative analysis, resulting in 15 proteins that differentiate S. diversa from S. saitoi. On another angle, it was examined the effect of S. diversa in the growth and viability of S. ludwigii and Z. bailii in different culture conditions and in different modes of growth (planktonic and in a mixed biofilm). The results obtained allowed us to conclude that under the conditions utilized S. diversa did not significantly inhibited growth of S. ludwigii or Z. bailii during planktonic growth, but caused significant reduction in viability of the spoilage yeasts while in a biofilm. This result suggest that cell-cell contact is an important mechanism for the biocontrol activity of S. diversa.engLeveduras não-SaccharomycesSaturnispora diversaleveduras de deterioraçãoZygosaccharomyces bailiiSaccharomycodes ludwigiiTeses de mestrado - 2024master thesis203741617