(−)-Viriditoxin

(−)-Viriditoxin is a mycotoxin originally isolated from A. viridinutans that has antibacterial and antiproliferative activity.^1,2,3,4 It is active against methicillin-sensitive and -resistant S. aureus (MSSA and MRSA, respectively), tetracycline-sensitive and -resistant Staphylococcus, vancomycin-sensitive and -resistant Enterococcus, and penicillin-sensitive and -resistant S. pneumoniae (MICs = 2-32 μg/ml).² (−)-Viriditoxin is also active against fish pathogens, including S. iniae and S. parauberis (MICs = 0.16-0.21 μg/ml).³ It inhibits polymerization and the GTPase activity of E. coli FtsZ, a tubulin-like GTPase involved in bacterial cell division (IC₅₀s = 8.2 and 7 μg/ml, respectively).² (−)-Viriditoxin inhibits proliferation of human DU145, LNCaP, and PC3 prostate cancer cells (IC₅₀s = 5.36, 0.63, and 7.6 μM, respectively) .⁴ It is also toxic to mice (LD₅₀ = 2.8 mg/kg, i.p.).⁵

WARNING This product is not for human or veterinary use.

1. Weisleder, D., and Lillehoj, E.B. Structure of viriditoxin, a toxic metabolite of Aspergillus viridi-nutans. Tetrahedron Lett. 48, 4705-4706 (1971).

2. Wang, J., Galgoci, A., Kodali, S., et al. Discovery of a small molecule that inhibits cell division by blocking FtsZ, a novel therapeutic target of antibiotics. The Journal of Biological Chemisty 278(45), 44424-44428 (2003).

3. Noh, T.H., Sen, L., Hong, J., et al. Antibacterial activities of viriditoxin congeners and synthetic analogues against fish pathogens. Bioorg. Med. Chem. Lett. 27(22), 4970-4974 (2017).

4. Kundu, S., Kim, T.H., Yoon, J.H., et al. Viriditoxin regulates apoptosis and autophagy via mitotic catastrophe and microtubule formation in human prostate cancer cells. Int. J. Oncol. 45(6), 2331-2340 (2014).

5. Wong, D.T., and Hamill, R.L. Viriditoxin induces swelling and ATPase by activation of calcium transport in liver mitochondria. Biochem. Biophys. Res. Commun. 71(1), 332-338 (1976).