Jadomycin B, is produced by Streptomyces venezuelae fermentation. It is an angucycline antibiotic containing an unusual 8H-benz[b]oxazolo[3,2-f]-phenanthridine ring system and a rare carbohydrate, digitoxose.1,2
Jadomycin B displays antimicrobial, anti-tumor, aurora-B kinase inhibition, DNA cleaving and more activities.3,4,5,6
Jadomycin B was found to be active against a variety of staphylococci, including methicillin-resistant Staphylococcus aureus in a MIC of 1μg/ml.3 In addition, its anti-tumor activity was demonstrated as it kills drug-sensitive and multidrug-resistant breast cancer cell, through inhibition of type II topoisomerases and the induction of DNA damage and apoptosis. Jadomycin B (15 mM), 24-hour treatment significantly lowered the levels of topoisomerase IIa protein versus the vehicle control.4
It was also shown that Jadomycin B inhibits Aurora-B kinase activity by phosphorylation of histone H3 on Ser10 in a dose-dependent manner (10μg /mL Jadomycin B reduced H3 phosphorylation by 70%).5
Jadomycin B was also found to cleave DNA in the presence of Cu (II) by reducing it to Cu(I) which can further react with H2O2 to form hydroxyl radicals that causes DNA strand scission without the requirement of any external reducing agent. The EC50 value of Jadomycin B for single-strand scission was approximately 1.7μM.6
