Co-evolutionary insights from a yeast-microalgae mutualism: Identification of mutations that may improve cooperativity by Rene NAIDOO-BLASSOPLES

Abstract: Yeast and microalgae each exhibit unique physiological and biotechnological attributes and provide a good model system for the study of autotroph and heterotroph interactions. Yeasts are widely used in fermentation-based processes, whereas microalgae are used for the production of valuable metabolites and for treating wastewater. Due to their diverse range of applications, there has been sustained interest in the creation of functional yeast and microalgae ecosystems for use in biotechnological processes. However, molecular insights into how these autotroph-heterotroph mutualisms are established and maintained, as well as interaction-specific effects are poorly understood.
Through the use of ecosystem engineering and co-evolution we have established a platform which allows us to evaluate co-evolutionary impacts on co-cultured populations of yeast and microalgae. A synthetically engineered mutualism between Saccharomyces cerevisiae and Chlorella sorokiniana based on the reciprocal exchange of carbon and nitrogen was established. Following 100 generations of co-evolution in a continuous culture bioreactor, selected yeast and microalgae were isolated and comparative genomic analysis performed on the yeast. This led to the identification of several SNPs with two potentially high impact SNPs, HNM1 and PSP1 identified. The role of these genes and their impact on co-operative behaviour between yeast and microalgae are currently being investigated by using a combination of molecular and microbiological approaches to re-engineer these SNPs into the parent strain and to evaluate the impact on co-culture phenotypes. 

Biography: Dr Rene Naidoo-Blassoples holds a PhD in Molecular and Cell Biology from the University of Cape Town and is currently employed as a Senior Research Assistant at Stellenbosch University. Her work explores the use of synthetic ecosystems to study microbial interactions between yeast and microalgae using basic design principles such as directed selection, engineered symbioses, and tailored growth conditions. Central to her research is the impact of co-evolution in multi-species ecosystems, and how this shapes ecosystem structure and function. These insights provide fundamental knowledge that can be used to improve biotechnological processes and aid in the development of integrated multi-species ecosystems for industry and agriculture.

Dr Rene NAIDOO-BLASSOPLES is Senior Research Assistant at Stellenbosch University, more details -> Rene NAIDOO-BLASSOPLES