IONOMYCIN, A NEW POLYETHER ANTIBIOTIC

Ionomycin, a new polyether antibiotic with a high affinity for calcium ions, is obtained in pure form from fermentation broths of Streptomyces conglobatus sp. nov. TREJO by solvent extraction. It is unique amongst known polyether antibiotics in that it has a UV absorption maximum at 300 nm, thereby distinguishing it from other antibiotics of its class. The Ca salt has the molecular formula C41H70O9Ca. Ionomycin is a narrow spectrum antibiotic being active against Gram-positive bacteria.