calicheamicin

Description: Calicheamicin, formerly 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 analogueous 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.

References: Singh S, Michalska K, Bigelow L, Endres M, Kharel MK, Babnigg G, Yennamalli RM, Bingman CA, Joachimiak A, Thorson JS, Phillips GN Jr. Structural Characterization of CalS8, a TDP-alpha-D-Glucose Dehydrogenase Involved in Calicheamicin Aminodideoxypentose Biosynthesis. J Biol Chem. 2015 Oct 23; 290(43):26249-58. doi: 10.1074/jbc.M115.673459. Epub 2015 Aug 3. PubMed PMID: 26240141; PubMed Central PMCID: PMC4646273.