The complete synthetic pathway of echinacoside from Cistanche deserticola and its de novo biosynthesis in yeast.

Echinacoside (ECH), a representative phenylethanol glycoside, exhibits diverse pharmacological properties and is used in the treatment of neurodegenerative disorders (e.g., Parkinson's and Alzheimer's diseases), ischemic brain injury, and cancer. The growing therapeutic demand for ECH has highlighted the need for scalable production. However, conventional methods face major limitations: chemical synthesis is hindered by the compound's structural complexity, and the yield of ECH extracted from plants is naturally low due to the host-dependent growth of Cistanche deserticola (C. deserticola), a parasitic desert plant. To establish a sustainable microbial production platform, we first deciphered the biosynthetic pathway of ECH in C. deserticola by integrating metabolomics analyses of plant tissues and callus cultures. This enabled the identification of key precursors, enzymatic steps, and regulatory mechanisms. Leveraging this knowledge, we engineered the pathway in Saccharomyces cerevisiae, achieving de novo ECH biosynthesis at a titer of 7.52 ± 1.42 mg/l. This study lays the foundation for industrial-scale ECH production and deepens our understanding of bioactive compound biosynthesis in parasitic plants, offering insights for future pathway engineering efforts.