Archazolids, new cytotoxic macrolactones from Archangium gephyra (Myxobacteria). Production, isolation, physico-chemical and biological properties

J Antibiot (Tokyo). 2003 Jun;56(6):520-5. doi: 10.7164/antibiotics.56.520.


Novel cytotoxic compounds, archazolid A and B, were isolated from the culture broth of strains of the myxobacteria Archangium gephyra and Cystobacter sp. Archazolids consist of a macrocyclic lactone ring with a thiazole side chain and showed high activity against mammalian cells. The IC50 values with different cell lines ranged from 0.1 to 1 ng/ml. An incubation of PtK2 potoroo cells with archazolid A (5 ng/ml) led to the formation of vacuoles in the ER, a phenomenon that is typical for inhibitors of V-ATPases, like concanamycin and bafilomycin. We therefore assume that archazolid is an inhibitor of the V-ATPase of higher cells.

MeSH terms

  • Animals
  • Antibiotics, Antineoplastic* / chemistry
  • Antibiotics, Antineoplastic* / isolation & purification
  • Antibiotics, Antineoplastic* / therapeutic use
  • Female
  • Fermentation
  • Fibroblasts / drug effects
  • Humans
  • Lactones* / chemistry
  • Lactones* / isolation & purification
  • Lactones* / therapeutic use
  • Male
  • Mice
  • Microbial Sensitivity Tests
  • Tumor Cells, Cultured / drug effects*


  • Antibiotics, Antineoplastic
  • Lactones