Calicheamicin, also known as Calicheamicin gamma(1,I) or Calichemicin gamma1, is an potent enediyne antitumor antibiotics derived from the bacterium Micromonospora echinospora. Calicheamicin targets DNA and cause strand scission. Calicheamicin binds with DNA in the minor groove, wherein it then undergos a reaction analogous to the Bergman cyclization to generate a diradical species. This diradical, 1,4-didehydrobenzene, then abstracts hydrogen atoms from the deoxyribose (sugar) backbone of DNA, which ultimately leads to strand scission. The specificity of binding of calicheamicin to the minor groove of DNA is due to the aryltetrasaccharide group of the molecule.

Providing storage is as stated on the product vial and the vial is kept tightly sealed, the product can be stored for up to 24 months.
Wherever possible, you should prepare and use solutions on the same day. However, if you need to make up stock solutions in advance, we recommend that you store the solution as aliquots in tightly sealed vials at -20°C. Generally, these will be useable for up to one month. Before use, and prior to opening the vial we recommend that you allow your product to equilibrate to room temperature for at least 1 hour.