Transcriptional regulation of genes required for antibiotic TA synthesis in Myxococcus xanthus

Regulatory mutants were isolated for six genes required for the production of antibiotic TA in Myxococcus xanthus, using Tn5lac as a promoter probe. Two of the regulatory mutants were closely linked to their corresponding Tn5lac insertions and three were separated by at least 40 kb from their original insertions. All of the β-galactosidase-overproducing mutants showed higher specific activities than their parent strains in three different media. The specific activity was higher throughout the growth cycle, starting earlier and finishing higher. In addition to helping to understand the mechanism of repression of TA genes, the mutants are potentially useful in the construction of antibiotic-overproducing strains.