Fig. 2
Characterizing strains N6D (with “constitutive” gene overexpression constructs) [23] and NC1D (with copper-inducible gene overexpression constructs): a the copper-inducible expression cassettes in plasmids pPMVAugw, pPMVAd36 and pJT3; b nerolidol titre at 24 and 72 h; c growth curves over batch cultivation; d mRNA levels in strain N6D in the exponential phase (EXP) and the ethanol phase (ETH, at 48 h); e mRNA levels in the strain NC1D in the pre-culture (without adding copper; un-induced) and in two-phase cultivation (with copper added; induced; at 10 or 36 h). Two-phase flask cultivation on 20 g L−1 glucose was employed; for the cultivation of NC1D, 100, 100 and 200 μM (final concentration) copper sulphate was added sequentially at 5, 10 and 24 h. mRNA levels were measured by quantitative real-time PCR. Mean values ± standard deviations are shown (N ≥ 3)