Establishing Saccharomyces cerevisiae as a host for renewable acrylic acid production

Acrylic acid (AA) is an important industrial chemical with a wide range of applications and growing market demand. To explore sustainable production routes, we investigated Saccharomyces cerevisiae as a host organism for direct fermentative production of AA. We first assessed the native tolerance of the host to AA and employed adaptive laboratory evolution to obtain strains with improved phenotypes. Whole-genome sequencing of evolved mutants showed that tolerance is linked to the mitochondrial genes ACH1 and ETR1, implicating the prevention of toxic intermediate AA-CoA accumulation as a key tolerance mechanism. While the wildtype strain was able to degrade AA via ACH1, a respective knockout mostly abolished degradation. Next, we screened three biosynthetic pathways and identified the β-alanine route as the most promising for direct fermentative production of AA. Finally, batch fermentation in shake flasks yielded titres of 30 mg L⁻¹ AA. These findings provide new insights into the genetic basis of AA tolerance in yeast and establish a foundation for developing S. cerevisiae as a platform for renewable AA production.