Open AccessFunctions of the Peptide Antibiotics Tyrocidine and Gramicidin
Author(s) -
HANSEN Jutta,
PSCHORN Wolfgang,
RISTOW Hansjürgen
Publication year - 1982
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1982.tb06776.x
Subject(s) - peptide , gramicidin s , nuclease , dna , gramicidin , biochemistry , rna , gel electrophoresis , chemistry , biology , microbiology and biotechnology , gene , membrane
The peptide antibiotic tyrocidine which is produced by Bacillus brevis and is probably involved in sporogenesis, unwinds superhelical plasmids in vitro at low peptide: DNA ratios, as found by gel electrophoresis. At higher peptide concentrations, the DNA is packed tightly leading to apparent nuclease stability of the complex and inhibition of RNA synthesis. The addition of the linear gramicidin, another peptide antibiotic synthesized by the same bacterial strain, partially restores transcription by breaking down the tightly packed DNA · peptide complex. The complexed DNA, after nuclease digestion, is retained on a nitrocellulose filter, but loses its affinity for the filter in the presence of gramicidin. The results are discussed with respect to possible functions of the two peptides within in the cell.