Development of Komagataella phaffii as a cell factory for efficient de novo production of β-caryophyllene

β-Caryophyllene is a natural bicyclic sesquiterpene found in a large number of plants around the world. It has anti-inflammatory, anticancer and analgesic biological activities associated with its important medicinal value, and has also attracted attention in the field of bioenergy with high energy density. Due to the low amount of β-caryophyllene in plants and complex purification process, microbial biosynthesis is considered as a promising alternative for the industrial development of β-caryophyllene. Komagataella phaffii has a robust transcriptional regulatory system and has many advantages in protein expression, high-density culture, making it suitable for large-scale industrial production. However, there are no systematic studies on the efficient biosynthesis of β-caryophyllene in K. phaffii. In this study, firstly, farnesyl diphosphate synthase ERG20 and β-caryophyllene synthase AaCPS were fused and expressed with different linkers. Secondly, we enhanced the mevalonate pathway and inhibited the branch pathway. At last, the copy number of ERG20-(PA)5-AaCPS were adjusted for the biosynthesis of β-caryophyllene, a highly efficient β-caryophyllene production strain AaCPS16 was constructed. AaCPS16 could produce 136.4 mg/L β-caryophyllene in shake flask level, which was 37 times higher than the initial strain AaCPS1. To the best of our knowledge, this is the first report of caryophyllene biosynthesis in Komagataella phaffii. This established a good foundation for the synthesis of sesquiterpenes in K. phaffii.