Development of an alternative metabolic pathway for olefin production from glycerol in yeast

• Grant number: 24/18815-5
• Support Opportunities: Scholarships in Brazil - Master
• Start date: May 01, 2025
• End date: February 28, 2027
• Field of knowledge: Biological Sciences - Genetics - Molecular Genetics and Genetics of Microorganisms
• Principal Investigator: Wesley Cardoso Generoso
• Grantee: Júlio César Bueno da Silva Filho
• Host Institution: Centro Nacional de Pesquisa em Energia e Materiais (CNPEM). Ministério da Ciência, Tecnologia e Inovação (Brasil). Campinas , SP, Brazil

Abstract

Terminal alkenes (a-olefins) are an example of a hydrocarbon that can be produced by biotechnological routes and are key molecules for the production of chemical derivatives, representing a significant reduction in the use of fossil resources. The use of fatty acid decarboxylases (OleT), which generate a-olefins as a product, is a promising alternative for the sustainable production of these compounds. In addition, the use of biosynthetic pathways in microorganisms allows hydrocarbons to be produced from cheap carbon sources other than vegetable oil and sugars. Thus, the main objective of this project is to develop a synthetic pathway in Saccharomyces cerevisiae to produce a-olefins from glycerol. Glycerol is a waste byproduct that is generated in abundance in the production of biodiesel, and in a biorefinery concept, it is essential to valorize it, although it is not effectively metabolized by yeasts. Methodologically, a deviation from the glycerol assimilation route will be used, using an alditol oxidase (AldO), which generates glycerate and hydrogen peroxide in this conversion. The hydrogen peroxide is used as a cosubstrate by the decarboxylase, generating alkenes, while glycerate can be phosphorylated and returned to glycolysis, without the excessive generation of NADH cofactors, the main cofactor used for ethanol production, and thus be able to divert the metabolism towards the production of fatty acids. The coupled reaction of the AldO and OleT enzymes has already been achieved, in a not yet optimized manner, in a yeast strain initially unable to grow on glycerol. This project proposes strategies for optimizing this glycerol consumption pathway and improving it for the specific production of alkenes.