posted on 2021-01-04, 21:15authored byMin Liu, Yang-Chen Lin, Jiao-Jiao Guo, Meng-Meng Du, Xinyi Tao, Bei Gao, Ming Zhao, Yushu Ma, Feng-Qing Wang, Dong-Zhi Wei
Patchoulol
is a tricyclic sesquiterpene widely used in perfumes
and cosmetics. Herein, comprehensive engineering strategies were employed
to construct an efficient yeast strain for patchoulol production.
First, a platform strain was constructed via pathway
modification. Second, three off-pathway genes were deleted, which
led to significant physiological changes in yeast. Further, strengthening
of the ergosterol pathway, enhancement of the energy supply, and a
decrease in intracellular reactive oxygen species were implemented
to improve the physiological status of yeast, demonstrating a new
promotive relationship between ergosterol biosynthesis and synthesis
of patchoulol. Moreover, patchoulol synthase was improved through
protein modification and Mg2+ addition, reaching a final
titer of 141.5 mg/L in a shake flask. Finally, a two-stage fermentation
with dodecane addition was employed to achieve the highest production
(1632.0 mg/L, 87.0 mg/g dry cell weight, 233.1 mg/L/d) ever reported
for patchoulol in a 5 L bioreactor. This work lays a foundation for
green and efficient patchoulol production.