METABOLIC ENGINEERING OF Saccharomyces cerevisiae FOR PRODUCTION OF ADIPIC ACID FROM RENEWABLE SOURCES
Conference poster, 2014
Adipic acid is a six carbon long dicarboxylic acid, considered to be the most important synthetic dicarboxylic acid annually produced, according to the International Energy Agency (IEA). The global production of adipic acid had in 2010 a volume of 2.8 million tonnes, for a total market price of 4.9 billion USD. The current production of adipic acid relies on non-renewable fossil raw materials, leading to emission of the greenhouse gases carbon dioxide and N2O. In addition, the production starts from benzene, whose use has several health related negative implications. This project aims to create a greener process for production of adipic acid developing a fermentation-based process using Swedish domestic renewable raw materials, such as forest residues and/or algae. These materials will be used to establish a biorefinery, wherein the fermentation process for the biosynthesis of adipic acid will represent the core process. Our current strategy is based on the generation of genetically modified strains of the yeast Saccharomyces cerevisiae, harbouring heterologous enzymatic activities allowing the conversion of lysine into adipic acid. This system is our first choice and will also work as proof-of-concept for bio-based production of adipic acid. Here we present the metabolic engineering strategy we are pursuing, based on two possible metabolic pathways for conversion of lysine into adipic acid. Preliminary results on the effect of adipic acid on S. cerevisiae physiology, lysine uptake, the expression of the heterologous genes of choice, and the conversion of lysine into adipic acid precursors are presented.