Inhibition of RNA and DNA polymerase reactions by pluramycin A

Abstract

Pluramycin A, isolated from the culture of Streptomyces pluricolorescens by Maeda et al (19561, is a basic antibiotic of orange needle crystals. The antitumor and antibacterial activity was reported by Takeuchi et al (1957). Lein et al (1962) observed phage induction of lysogenic bacteria by pluramycin. We investigated the activity of pluramycin A on macromolecular syntheses and observed that the antibiotic inhibits both protein and nucleic acids syntheses in the intact cells of bacteria. The effects were further investigated, using cell-free systems. The results are described in this communication. Protein synthesis was not significantly affected in bacterial cell-free systems but RNA and DNA polymerase reactions were markedly inhibited by the antibiotic, which was suggested to bind with DNA by the thermal transition curve. Effects on protein synthesis in cell-free systems from E. coli: Pluramycin A was observed to exhibit no significant effects on 14C-leucine incorporation into protein and polyuridylate-directed polyphenylalanine synthesis in cell-free systems obtained from exponentially growing cells of E. coli B. The method employed principally followed the one developed by Nirenberg and Matthaei (1961). The results are summarized in Tables 1 and 2.