Overexpression of C. zofingiensis DGATs in the yeast strain INVSC1 and marine alga N. oceanica

The plasmids pYES2-CzDGAT1A and pYES2-CzDGTT5 mentioned above were transformed into the TAG-producing S. cerevisiae strain INVSC1 using S.c. EasyComp™ Transformation Kit (Invitrogen). Transformants were selected on SD/-ura plates and verified by colony PCR. The expression of C. zofingiensis DGATs in yeast was induced by 2% (w/v) galactose.

For the expression of C. zofingiensis DGATs in the oleaginous alga N. oceanica, the coding sequence of CzDGAT1A was amplified and cloned into the overexpression vector as described in our previous study [27]. Nuclear transformation of N. oceanica was performed by electroporation according to Li et al. [68]. Transformants were selected on modified F/2 plates with 2.5 μg mL⁻¹ zeocin (Life Technologies, CA, USA) and verified by genomic PCR. Quantitative real-time PCR was employed to determine the overexpression level of CzDGAT1A.