Ionomycin from Streptomyces conglobatus

Ionomycin from Streptomyces conglobatus has been used:

• in magnesium-ionomycin treatment experiments
• as a supplement in calcium-free Dulbecco′s modified Eagle medium (DMEM) for ionophore treatment
• in the restimulation of peripheral blood mononuclear cells (PBMCs) to analyze cytokine production using flow cytometry (FCM)
• as a calcium ionophore to treat oocytes to perform intracytoplasmic sperm injection (ICSI) combined with assisted oocyte activation (AOA)

Ionomycin is a polyether antibiotic and an ionophore produced by the bacterium Streptomyces conglobatus. This Ca²⁺ ionophore is more effective than A23187 as a mobile ion carrier for Ca²⁺. It is non-fluorescent. It induces apoptotic degeneration of embryonic cortical neurons. Ionomycin has been shown to induce central demyelination, inhibit adrenal bovine TREK-1 channels, and regulate cell division of mature human B cells. It is used to study the effects of calcium flux on endoplasmic reticulum (ER) stress, mitochondrial stress, and intrinsic apoptosis mechanisms. It also stimulates the intracellular production of cytokines, interferon, perforin, interleukin-2 (IL-2), and IL-4 usually in conjunction with PMA.

Ionomycin is highly specific for divalent cations. It may have antiproliferative effects on the human bladder cancer cell line both in vitro and in vivo. Ionomycin functions as an apoptosis inducer which was suggested to act by activation of a latent, calcium-responsive endonuclease.