Analysis of metabolic pathways of Saccharomyces cerevisiae in alcoholic fermentation to mitigate glucose rise in grapes due to global warming effects

• Autor(a) principal: Magalhães, João Pedro Zamith Piedade Ribeiro
• Data de Publicação: 2021
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10348/10997
• topic: Global Warming; Systems Biology

In the modern era, due to human activity and consequent pollution, Earth’s climate has been severely impacted. A direct consequence of this change is Global Warming, the gradual heating of the planet’s surface, oceans, and atmosphere. This rise in temperature impacts all the biosphere, including humans, animals, and crops. One of these crops, the grape, is responsible for one of the world’s most renowned alcoholic beverages: wine. This alcoholic drink has accompanied the human species from ancient times until now, representing today, a gigantic industry worth billions of dollars. In recent years this industry came across some new challenges caused by Global Warming, namely, the higher concentration of glucose in grapes and the consequent rise of ethanol concentrations in wine. The negative consequences presented by this new challenge are vast, ranging from damages to the sensory profile of the wines, public health concerns, and higher taxation of wine products. The present dissertation tackles this emerging problem through Systems Biology and Metabolic Engineering approaches to study strategies that mitigate these changes by manipulating yeast metabolism. The pipeline of this study involves the identification and simulation of low-ethanol metabolic engineering strategies. This framework allowed us to simulate genetic and environmental conditions and analyze the impact of each strategy in the yeast’s metabolism. The results obtained showed that the most promising yeast strains to fit the needs of winemaking were the GPD1 and HC23 approaches. These results showed compliance with the literature in several parameters ensuring the reliability of the simulation and finding a strong similarity between the experimental bibliographic data and the in silico simulation results. These results corroborated with the scientific data regarding biomass values, ethanol production and glycerol yield. The results obtained in this work sustain the hypothesis that these methods can be a great advantage to the wine industry. Not only making the process more effective but possibly giving the wine healthier properties and a more predictable sensory profile. It is possible to say that systems and synthetic biology-based strategies like the one explored in this thesis will be impactful not only in the wine industry but in the future of our society.