Transcript analysis of err1 in parental and recombinant T. reesei strains. The T. reesei wild-type strain (WT) and preselected recombinant strains derived from transformation of the wild-type (a, b) or of Rut-C30 (c, d), which are expressing err1 either under the constitutive pki promoter (a, c) or under the inducible bxl1 promoter (b, d), respectively, were cultivated in shake flasks on D-xylose (blue bars) for 30 h (wild-type) or 72 h (Rut-C30) and on birch-wood xylan (red bars) for 48 h (wild-type) or 72 h (Rut-C30). Strains chosen for further experiments are framed in yellow. The transcript analysis was performed by qPCR using sar1 and act1 as genes for data normalization and levels always refer to the wild-type strain on the respective carbon source (indicated by a blue and red asterisk). Results are given as relative transcript ratios in logarithmic scale (lg). The values are means from three measurements. Error bars indicate standard deviations. Biological experiments (cultivations) were performed in duplicates.