Systematic engineering of the sterol synthesis pathway for Saccharomyces cerevisiae promotes the efficient production of β-caryophyllene

β-caryophyllene, a plant-derived sesquiterpene, serves as a food flavoring, anti-inflammatory agent, antioxidant, and high-energy fuel source. Extraction of β-caryophyllene from plants is a costly and inefficient process. Therefore, microbial cell factories have been employed for the production of β-caryophyllene. However, the limited yield is insufficient for its industrial application. In this study, we balanced the utilization of cellular resources for growth and production by systematically regulating the sterol synthesis pathway to maximize the synthesis of β-caryophyllene. In the competitive pathways concerning sterol and fatty acid synthesis, genes expression was suppressed by substituting the original promoters with a glucose-sensing promoter P HXT1 and a sterol synthesis promoter P ERG7 , respectively. This approach effectively increased the production of β-caryophyllene by 6.8 times, reaching 854.7 mg/L. Engineering glucose-sensing pathway altered the strength of P HXT1 , resulting in an increase in β-caryophyllene production to 1.25 g/L. The cell growth and β-caryophyllene production were further boosted through diploid fusion, resulting in 21.4 g/L β-caryophyllene in fed-batch fermentation. This represents the highest reported production of β-caryophyllene to date. This study provides a valuable reference for the production of sesquiterpenes in microbial cell factories.