Systematic Engineering to Enhance β-Myrcene Production in Yeast.

β-Myrcene is an important monoterpene compound widely used in the fragrance, agricultural, and food industries. The microbial production of β-myrcene conforms to the trend of green biological manufacturing, which has great potential for development. The poor catalytic activity of β-myrcene synthase (MS) and the insufficient supply of precursors are considered to be the bottlenecks of β-myrcene production. Here, source screening, subcellular localization, enzyme fusion, and precursor-enhancing strategies were integrated for β-myrcene biosynthesis with Saccharomyces cerevisiae . The β-myrcene titer gradually increased by 218-fold (up to 63.59 mg/L) compared to that of the initial titer of the shake flask. Moreover, the titer reached 66.82 mg/L after the addition of antioxidants (1 mM glutathione, GSH, and 1% butylated hydroxytoluene, BHT). Ultimately, 142.64 mg/L β-myrcene in S. cerevisiae was achieved in 5.0 L of fed-batch fermentation under a carbon restriction strategy, which was the highest reported titer in yeast thus far. This study not only established a platform for β-myrcene production but also provided a reference for the efficient biosynthesis of other monoterpene compounds.