Abstrakt

Improvement of B-Carotene Production in Yarrowia lipolytica Through Assembling Multiple Copies of B-Carotene Biosynthesis Genes from Blakeslea trispora

Shengming Yin, Yuanjie Wu, Songbai Yang and Shaoxin Chen

Multiple copies of β-carotene biosynthesis genes from commercially important fungi Blakeslea trispora are integrated in Yarrowia lipolytica to produce β-carotene. β-Carotene biosynthesis genes from B. trispora or Mucor circinelloides were expressed in Y. lipolytica respectively, and carRA and carB from B. trispora showed higher activity for production of β-carotene (4.35 mg/l). To produce higher quantities of β-carotene, the engineered strains harboring different copies of carRA, carB, geranylgeranyl diphosphate synthase gene (GGS), and HMG-CoA reductase gene (HMG) were constructed to investigate the yield of β-carotene. The engineered strain YC607, with three copies of carRA, carB, and GGS and two copies of HMG could produce 72.89 mg/l of β-carotene during shake flask culture. Furthermore, 613.87 mg/l of β-carotene was obtained with fed-batch fermentation by feeding glycerol. β-Carotene biosynthesis genes from B. trispora can be expressed in Y. lipolytica, and multiple copies of β-carotene synthesis genes can produce high amounts of β-carotene.