Determination of Copy Number of Target Carbohydrase Genes in the Penicillium verruculosum fungus Recombinant Strains

The protein profiles of the culture liquids of recombinant Penicillium verruculosum strains that secreted an Aspergillus niger β-glucosidase (BGL series) or a Penicillium canescens xylanase A (XYLA series) have been previously analyzed. It was shown that the producers were divided into two groups according to the target protein content: 75-85% (1) and no more than 15% (2). It was established in this work that the copy number of the target gene bgll in the recombinant strains correlated with the β-glucosidase content in the BGL-F10 and BGL-F12 enzyme preparations. However, this proportion was violated in the direction of decreasing the xylanase A relative amount: the target enzyme content of 50% and 17% in the XylA3 and XylA4 preparations corresponded to 20-22 and 6 copies, respectively, of the xylA gene. We believe that this effect is a result of titration of positive transcription factors in the P. verruculosum XylA3 strain containing 20 to 22 copies of the cbhl gene promoter. Penicillium verruculosum, real-time PCR, gene copy number This work was partially supported by the Russian Foundation for Bsic Research (Project number: 18-29-07070).