Sustainable Production\nof Shinorine from Agricultural\nWastes Using Engineered Saccharomyces cerevisiae Expressing Novel d‑Alanine‑d‑alanine\nLigase from Pseudonocardia pini

Shinorine, a compound known for its protective properties\nagainst\nUV radiation, is widely used in cosmetics and pharmaceuticals. Despite\nthe construction of various recombinant Saccharomyces\ncerevisiae strains for shinorine production, achieving\nindustrial-scale yields remains a challenge. In this study, genes\nencoding enzymes (DDGS, O-MT, and ATP-grasp enzyme) from Actinosynnema mirum were introduced into S. cerevisiae DXdT to enable the heterologous conversion\nof sedoheptulose 7-phosphate to mycosporine-glycinethe direct\nbiosynthetic precursor of shinorine. Subsequently, a novel d-alanine-d-alanine ligase from Pseudonocardia\npini was introduced to produce shinorine. The engineered\nstrain (DXdT-MG-mi89-PP.ddl) produced 267.9 mg/L shinorine with a\n48.6 mg/g dry cell weight (DCW) content in a medium supplemented with\nlignocellulosic hydrolysate derived from rice straw. Notably, the\nrecombinant strain produced 1.7 g/L shinorine with a 79.1 mg/g DCW\ncontent from a corn steep liquor medium with a mixture of glucose\nand xylose. These results support the idea that sustainable shinorine\nproduction from agricultural wastes holds significant promise for\nindustrial applications.