70563-58-5

Herbimycin A (70563-58-5) is an ansamycin antibiotic. Inhibits HSP90 and associated client proteins including v-Src, Bcr-Abl, Raf-1 and ErbB2.1,2 Herbimycin A reverts tyrosine kinase-induced oncogenic transformation without direct inhibition of phosphorylation activity.1 Inhibits angiogenesis in a rat retinopathy model.3

Herbimycin A is a benzoquinone ansamycin antibiotic from Streptomyces. It has herbicidal activity and acts as a cell-permeable inhibitor of non-receptor tyrosine kinases and the heat shock protein Hsp90. Herbimycin A inhibits Bcr-Abl with an IC50 value of 5 μM, a concentration that also effectively blocks Src, Yes, Fps, Ros, and ErbB but not protein kinases (PK) PKA, PKC, Rac, Myc, or Raf. Presumably through its effects on tyrosine kinase signaling, herbimycin A also impairs endothelial cell proliferation in the context of angiogenesis, NF-κB activation, phosphorylation of phospholipase C-γ1, and eggshell formation in schistosome parasites. Ansamycins, including herbimycin A and geldanamycin , bind Hsp90 and destabilize client proteins, including Src, Bcr-Abl, and ErbB2, leading to their ubiquitination and proteasomal degradation.

Herbimycin A is the major analogue of a complex of benzoquinone ansamycin antibiotics isolated from a Streptomyces hygroscopicus. Herbimycin A inhibits the 90-kDa heat-shock protein (Hsp90) which provides essential chaperone support to various signal transduction molecules, including certain steroid hormone receptors and select kinases. Herbimycin also inhibits protein tyrosine kinase and angiogenesis.

ChEBI: A 19-membered macrocyle incorporating a benzoquinone ring and a lactam functionality. It is an ansamycin antibiotic that induces apoptosis and displays antitumour effects.

A cell-permeable, potent inhibitor of protein tyrosine kinases. Inhibits p60^v-src (IC₅₀ = 12 μM) autophosphorylation. Irreversibly binds to the sulfhydryl groups of the kinase. Dose-dependently inhibits PDGF-induced phospholipase D activation (IC₅₀ = 8 μg/ml). Also, reported to inhibit c-src related bone resorption (IC₅₀ = 70 nM). Inhibits angiogenesis in chick chorioallantoic membrane and blocks anti-CD3 monoclonal antibody-induced apoptosis of thymocytes. Several mammalian cell lines transformed with tyrosine kinase oncogenes (src, abl, fps, ros, yes, erbB) show reversion from the transformed to the normal phenotype after treatment with herbimycin A.

Ansamycin antibiotic that acts as a Src family kinase inhibitor. Binds to the SH domain and inhibits the activity of p60 v-src and p210 BCR-ABL . Exhibits antiangiogenic activity in endothelial cells in vitro . Also inhibits Hsp90 and impairs recovery from heat shock.

Cell permeable: yes

Store at -20°C

1) Whitesell et al. (1994), Inhibition of heat shock protein HSP-90-pp60vsrc heteroprotein complex formation by benzoquinone ansamycins: essential role for stress proteins in oncogenic transformation; Proc. Natl. Acad. Sci. USA, 91 8324 2) Blagosklonny et al. (2002), Hsp-90-associated oncoproteins: multiple targets of geldanamycin and it’s analogs; Leukemia, 16 455 3) GW McCollum et al. (2004), Herbimycin A inhibits angiogenic activity in endothelial cells and reduces neovascularization in a rat model of retinopathy of prematurity; Exp. Eye Res., 78 987