thiostrepton and sporangiomycin

The antibiotics thiostrepton, siomycin, and sporangiomycin are closely related both in structure and in mode of action. Actinomycetes which produce this group of compounds possess ribonucleic acid-pentose methylases, which act upon 23S ribosomal ribonucleic acid and render ribosomes resistant to the action of these antibiotics. This is achieved via the formation of a single residue of 2'-O-methyladenosine per ribosome.

Topics: Actinomycetales; Anti-Bacterial Agents; Antibiotics, Antineoplastic; Drug Resistance, Microbial; Intercellular Signaling Peptides and Proteins; Methylation; Methyltransferases; Peptides; Ribosomes; RNA, Bacterial; RNA, Ribosomal; Streptomyces; Thiostrepton

Sporangiomycin and micrococcin inhibit the binding of aminoacyl-transfer ribonucleic acid into the ribosomal A site in intact bacterial protoplasts. They also prevent the assembly of [ribosome-elongation factor G-guanine nucleotide] complexes in vitro and compete with [(35)S]thiostrepton for ribosomal binding sites. We conclude that micrococcin and sporangiomycin block the ribosomal A site in the vicinity of the complex guanosine triphosphatase center and so resemble thiostrepton in their modes of action.

Topics: Anti-Bacterial Agents; Bacillus megaterium; Bacteriocins; Escherichia coli; Intercellular Signaling Peptides and Proteins; Peptides; Ribosomes; RNA, Bacterial; RNA, Transfer; Thiostrepton