Integrative metabolic and cellular organelle engineering for improving biosynthesis of flavonoid compounds in saccharomycescerevisiae

Abstract

Flavonoids, including dihydroflavonols and anthocyanins, are phenolic compounds with significant biological activity, playing a crucial role in the sensory characteristics and health benefits of wine. In this study, we selected the naringenin-producing strain HB52 （Saccharomyces cerevisiae） as the starting strain and introduced synthetic pathways for dihydroflavonols and anthocyanins, achieving de novo synthesis of various flavonoid compounds. To further optimize flavonoid production, we employed several strategies, including overexpressing 5-enolpyruvylshikimate 3-phosphate synthase to enhance metabolic flux, integrating NADPH regeneration genes, and using citric acid/isocitric acid transporter genes to increase the levels of cofactors. Additionally, organelle engineering was utilized to strengthen the β-oxidation pathway, thereby elevating the levels of precursors such as acetyl-coenzyme A (CoA) and malonyl-CoA. Engineered strains significantly improved their ability to synthesize various flavonoids directly from glucose. In the final engineered strains, the production levels of NAR, DHQ, and DHM in the dihydroflavonol-engineered strains reached 379.2 mg/L, 231.3 mg/L, and 284.8 mg/L, respectively. The anthocyanin-engineered strains achieved the highest yield of anthocyanin synthesized from glucose in S. cerevisiae, reaching 45.7 mg/L (33.4 mg/L for C3G and 12.3 mg/L for D3G). This study highlights the potential of metabolic and organelle engineering in S. cerevisiae to increase flavonoid production, offering new prospects for enhancing sensory quality and health benefits in the wine industry.