Large-Scale Transposition Mutagenesis of Streptomyces coelicolor Identifies Hundreds of Genes Influencing Antibiotic Biosynthesis.

Gram-positive bacteria produce thousands of bioactive secondary metabolites, including antibiotics. To systematically investigate genes affecting secondary metabolism, we developed a hyperactive transposase-based Tn transposition system and employed it to mutagenize the model species , leading to the identification of 51,443 transposition insertions. These insertions were distributed randomly along the chromosome except for some preferred regions associated with relatively low GC content in the chromosomal core.

Curing baldness activates antibiotic production.

Kalan and colleagues describe an unusual way of activating a "silent" gene cluster for the biosynthesis of a new antibiotic by analyzing and curing the aerial growth defect of an old Streptomyces isolate, Streptomyces calvus. This commentary addresses the broad scientific and historical context and practical and biological significance of this finding.

Developmental biology of Streptomyces from the perspective of 100 actinobacterial genome sequences.

To illuminate the evolution and mechanisms of actinobacterial complexity, we evaluate the distribution and origins of known Streptomyces developmental genes and the developmental significance of actinobacteria-specific genes. As an aid, we developed the Actinoblast database of reciprocal blastp best hits between the Streptomyces coelicolor genome and more than 100 other actinobacterial genomes (http://streptomyces.org.