title: The sorangicins, novel and powerful inhibitors of eubacterial RNA polymerase isolated from myxobacteria.
abstract: A new antibiotic, sorangicin, was isolated from the culture supernatant of the myxobacterium, Sorangium (Polyangium) cellulosum strain So cel2. It is a macrocyclic lactone carbonic acid and is produced in two structural variants, sorangicins A and B. In addition small quantities of the respective glycosides, sorangiosids A and B, may be found. The antibiotic acts mainly against Gram-positive bacteria, including myocobacteria, with MIC values between 0.01 and 0.1 microgram/ml, but at higher concentrations (MIC 3 approximately 30 micrograms/ml) Gram-negatives are also inhibited. Yeasts and molds are completely resistant. The new antibiotic is a specific inhibitor of eubacterial RNA polymerase which it blocks, however, only if added before RNA polymerization has started.
mesh_terms: D000617:Aminoglycosides; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D012321:DNA-Directed RNA Polymerases / Q000037:antagonists & inhibitors*; D005051:Eubacterium / Q000201:enzymology*; D006027:Glycosides / Q000302:isolation & purification / Q000494:pharmacology; D006094:Gram-Positive Bacteria / Q000187:drug effects; D009682:Magnetic Resonance Spectroscopy; D008826:Microbial Sensitivity Tests; D009231:Myxococcales / Q000254:growth & development*; D013329:Structure-Activity Relationship
chemical_list: D000617:Aminoglycosides; D000900:Anti-Bacterial Agents; D006027:Glycosides; C051799:sorangicin A; C052000:sorangicin B; D012321:DNA-Directed RNA Polymerases