Fig. 3.

Characterization of the metabolic flux of MVA pathway of industrial strains using squalene as the metabolic marker. (A) Increase in squalene content in yeast strains via engineering HMGR activity, NADPH regeneration and cytosolic acetyl‐CoA supply. (B) Verification of the transcription of EfHMGR, gapC and CDC19‐PDC1 in different strains. (C) Cell growth. (D) Squalene production. Yeast cells were cultivated in YPD at 30°C for 24 h. Data are presented as the means of three biological replicates. Error bars represent standard deviations (n = 3). Student’s t‐test was used for statistical analysis. The lower‐case letters a, b, c and d in (A) and (D) indicate significant differences among different strains (P < 0.05). NS indicates that there are no significant differences among the different strains.