6-Demethylchlortetracycline (6-DCT)， a tetracycline antibiotic produced by Streptomyces aureofaciens， is a crucial precursor employed for the semi-synthesis of tigecycline， minocycline， and amadacyclin (PTK 0796). In this study， the 6-DCT biosynthetic gene cluster (BGC) was cloned from genomic DNA of a high 6-DCT-producing strain， S. aureofaciens DM-1， using the transformation-associated recombination method. An extra copy of the 6-DCT BGC was introduced and integrated into the chromosome of S. aureofaciens DM-1. Duplication of the 6-DCT BGC resulted in a maximum increase of the 6-DCT titer by 34%.
6-Demethylchlortetracycline (6-DCT)， a tetracycline antibiotic produced by Streptomyces aureofaciens， is a crucial precursor employed for the semi-synthesis of tigecycline， minocycline， and amadacyclin (PTK 0796). In this study， the 6-DCT biosynthetic gene cluster (BGC) was cloned from genomic DNA of a high 6-DCT-producing strain， S. aureofaciens DM-1， using the transformation-associated recombination method. An extra copy of the 6-DCT BGC was introduced and integrated into the chromosome of S. aureofaciens DM-1. Duplication of the 6-DCT BGC resulted in a maximum increase of the 6-DCT titer by 34%.
