Effect of gramicidin S on the transcription system of the producer Bacillus brevis Nagano.
The effect of the peptide antibiotic gramicidin S, produced by Bacillus brevis Nagano, was tested on the transcription system of the producer by using in vivo, semi in vitro and in vitro systems for studies of RNA synthesis. The effects of other peptide antibiotics (linear gramicidin, tyrocidine and tyrothricin) were also tested for comparison. It was found that (a) RNA polymerase isolated from either gramicidin S-producing or non-producing strains had a similar structure and requirements and that (b) the presence of gramicidin S caused a very strong inhibition of the in vitro transcription system. We present evidence that this inhibition is most probably through formation of a complex between the antibiotic and the DNA. In vivo studies indicate that transcription during growth and sporulation is not affected by gramicidin S and the implication is made that gramicidin S inhibits transcription during germination and outgrowth.
M
M
Frangou-Lazaridis
B
B
Seddon
D001407:Bacillus / Q000187:drug effects* / Q000201:enzymology / Q000235:genetics; D004269:DNA, Bacterial / Q000378:metabolism; D012321:DNA-Directed RNA Polymerases / Q000378:metabolism; D006096:Gramicidin / Q000494:pharmacology*; D014158:Transcription, Genetic / Q000187:drug effects*; D014544:Uridine Triphosphate / Q000378:metabolism
D004269:DNA, Bacterial; D006096:Gramicidin; D012321:DNA-Directed RNA Polymerases; D014544:Uridine Triphosphate