2.2 Genetic transformation of Y. lipolytica
All plasmids constructed were transformed into the Y. lipolyticahost strain Po1g ΔLeu using the lithium acetate/single-strand carrier
DNA/PEG method (Chen, Beckerich, & Gaillardin, 1997). And single freshY. lipolytica colonies were picked from YNB selective plates and
inoculated into YNB seed media, which were grown at 30 °C for 48 h. For
tube test, 100 μL seed cultures were inoculated into 5 mL fermentation
media in 50 mL tube. 600 μL seed cultures were inoculated into 30 mL
fermentation media in 250 mL shake flasks with 250 rpm and 30 °C. Time
series samples were taken for analyzing biomass, sugar content, and
squalene titer.