Novobiocin Sodium (Albamycinsodium) binds to DNA gyrase and blocks adenosine triphosphatase (ATPase) activity. Novobiocin sodium is an antibiotic compound derived from Streptomyces niveus. It has a chemical structure similar to coumarin.

HSP90:700 μM (IC50)

Novobiocin also interacts with Hsp90, altering the affinity of the chaperone for geldanamycin and radicicol and causing in vitro and in vivo depletion of key regulatory Hsp90-dependent kinases including v-Src, Raf-1, and p185(ErbB2). Novobiocin interferes with association of the co-chaperones Hsc70 and p23 with Hsp90. [1] Novobiocin specifically inhibits the maturation of the heme-regulated eIF2alpha kinase (HRI) in a concentration-dependent manner. Novobiocin induces the dissociation of Hsp90 and Cdc37 from immature HRI, while the Hsp90 cochaperones p23, FKBP52, and protein phosphatase 5 remained associated with immature HRI. [2] Novobiocin causes morphological and biochemical changes which lead to induction of cell death exhibiting characteristic features of metazoan apoptosis. [3] Novobiocin, a HSP90 inhibitor, could decrease the expression of SMYD3 and dose dependently inhibit the proliferation and migration of MDA-MB-231 human breast cancer cells. Novobiocin can inhibit the migration of breast cancer cells and such event may involve the downregulation of SMYD3. [4] Novobiocin, an aminocoumarin antibiotic, interferes with heat shock protein 90 and hypoxia inducible factor dependent gene expression and thus compromises cell survival. Novobiocin (500 礛) results in a significant increase of [Ca(2+)]i, decrease of forward scatter, increase of annexin-V-binding and enhances ceramide formation. Novobiocin stimulates eryptosis, an effect at least in part due to entry of extracellular Ca(2+) and formation of ceramide. [5]