sweet-yeast: sweet but myco

Naturally derived sweet-tasting proteins, up to 100,000 times sweeter than traditional sugar, have received approval for human consumption by both the FDA and the European Union. These proteins stand apart from synthetic sweeteners, such as aspartame and sucralose, by not changing blood sugar levels or the composition of gut microbiota. As such, they are positioned as the forefront of next-generation, low-calorie sweetening options. However, the cost-effective production of these proteins on a large scale, particularly through microbial culture, remains economically challenging, which in turn limits their widespread use and full potential.

Our project aims to revolutionize the production of sweet-flavoured proteins by genetically enhancing the yeast strains Saccharomyces cerevisiae and its probiotic counterpart, Saccharomyces boulardii. Our strategy involves modifying the cell walls of these yeasts to increase their capacity for protein secretion and surface display. Initially, we will identify novel RNA-binding proteins that play a crucial role in maintaining cell wall stability and function as regulatory centers for cell wall properties. Leveraging this knowledge, we aim to significantly improve the secretion and surface display capabilities of S. cerevisiae for these sweet proteins. Subsequently, these advancements will be applied to S. boulardii, with modifications enabling it to bind sweet-flavoured proteins on its outer surface, effectively creating “sweet” probiotics. This innovative approach not only aims to enhance the viability of producing sweet-tasting proteins but also opens up new avenues of strategic engineering of probiotic surfaces, potentially leading to the development of novel, health-conscious sweetening solutions.

Project leader: Assoc Prof Igor Stuparević // Associate Professor, Laboratory for Biochemistry, Faculty of Food Technology and Biotechnology, University of Zagreb, Croatia

Associates:

Prof Renata Teparić // Full Professor, Laboratory for Biochemistry, Faculty of Food Technology and Biotechnology, University of Zagreb, Croatia

Asst Prof Bojan Žunar // Assistant Professor, Laboratory for Biochemistry, Faculty of Food Technology and Biotechnology, University of Zagreb, Croatia

Assoc Prof Marina Krpan // Associate Professor, Laboratory for Food Quality Control, Faculty of Food Technology and Biotechnology, University of Zagreb, Croatia

Ana Novačić, PhD // Postdoctoral Researcher, Laboratory for Biochemistry, Faculty of Food Technology and Biotechnology, University of Zagreb, Croatia

Mirta Boban, PhD // Research Associate, Croatian Institute for Brain Research, School of Medicine, University of Zagreb, Croatia

Assoc Prof Nino Sinčić // Associate Professor, School of Medicine, University of Zagreb, Croatia

Mihaela Pravica, mag. educ. biol. et chem. // PhD student, Croatian Institute for Brain Research, School of Medicine, University of Zagreb, Croatia

Have any questions or suggestions? Email us at sweetyeast[at]pbf.hr