The finite nature of fossil resources and the negative influence of CO2 emissions on the global climate are key drivers in development of new biological processes. These are based on renewable resources such as sugar, starch, and biomass and aim at replacing chemical production from fossil fuels. Polyacrylates are a substantial part of the different plastic varieties found on the market. This kind of plastic is derived from acrylic acid, which is currently produced from propylene, a by-product of ethylene and gasoline production. Annually, more than one billion kilograms of acrylic acid is produced and the market for acrylate products exceeds USD 100 billion.
As an alternative to oil and gas derived acrylic acid, 3-hydroxypropionic (3HP) acid produced from renewable sources is highly desired, because 3HP can easily be converted into acrylic acid. We are setting out to produce 3HP in yeast Saccharomyces cerevisiae. One main reason for selecting Baker's yeast as host organism is that yeast has a high tolerance towards low pH in comparison to bacteria, e.g. E. coli. Hence, it lowers the consumption of base for neutralization of growth media when compared to bacteria. The preferred engineered pathway towards 3HP has a substantial need for NADPH equivalents. Consequently, a yeast host with elevated NADPH availability is preferred. We will redirect several of the glycolysis steps in order to increase the NADPH generation per glucose molecule and thereby increase 3HP production.
We believe this strain will be of high interest for other NADPH demanding biosynthetic routes.