tmRNA of Streptomyces collinus and Streptomyces griseus during the growth and in the presence of antibiotics

Abstract

SummaryStreptomycetes are soil microorganisms with the potential to produce a broad spectrum of secondary metabolities. The production of antibiotics is accompanied by a decrease in protein synthesis, which raises the question of how these bacteria survived the transition from the primary to the secondary metabolism. Translating ribosomes incapable to properly elongate or terminate polypeptide chain activate bacterial trans‐translation system. Abundance and stability of the tmRNA during growth of Streptomyces collinus and Streptomyces griseus producing kirromycin and streptomycin, respectively, was analysed. The level of tmRNA is mostly proportional to the activity of the translational system. We demonstrate that the addition of sub‐inhibitory concentrations of produced antibiotics to the cultures from the beginning of the exponential phase of growth leads to an increase in tmRNA levels and to an incorporation of amino acids into the tag‐peptides at trans‐translation of stalled ribosomes. These findings suggest that produced antibiotics induce tmRNA that facilitate reactivation of stalled complex of ribosomes and maintain viability. The effect of antibiotics that inhibit the cell‐wall turnover, DNA, RNA or protein synthesis on the level of tmRNA was examined. Antibiotics interfering with ribosomal target sites are more effective at stimulation of the tmRNA level in streptomycetes examined than those affecting the synthesis of DNA, RNA or the cell wall.

New Alpiniamides From Streptomyces sp. IB2014/011-12 Assembled by an Unusual Hybrid Non-ribosomal Peptide Synthetase Trans-AT Polyketide Synthase Enzyme

“…The genome has a G + C content of 71.5%. The chromosome is predicted to contain 7.282 coding sequences, 5 rRNA clusters, 80 tRNA genes and one tmRNA gene ( Palecková et al, 2009 ). The analysis of the genome using antiSMASH software revealed that 29 gene clusters are involved in the biosynthesis of diverse secondary metabolites including terpenes, lanthipeptides, non-ribosomal peptides, and polyketides ( Supplementary Table S2 ).…”