Ionomycin

**Semantic type:** Amino Acid, Peptide, or Protein|Antibiotic|Pharmacologic Substance

**Definition:** A polyether antibiotic isolated from Streptomyces conglobatus sp. nov. Trejo with antineoplastic activity. Ionomycin is a calcium ionophore that increases intracellular Ca++ levels, possibly relating to endonuclease activation of lymphocytes and decreased ratio of Bcl-2 to Bax and ultimately apoptosis. In addition, this agent is used to investigate the role of intracellular calcium in cellular processes. (NCI)

**Synonyms:** - IONOMYCIN - ionomycin