Benastatin A is a polyketide synthase-derived benastatin that has been found inStreptomycesand has diverse biological activities.^1,2,3It inhibits glutathione S-transferase (GST; K_i= 5 µM for the rat liver enzyme).²Benastatin A is active against several bacteria, including methicillin-resistantS. aureus(MRSA; MIC = 3.12 µg/ml). It induces apoptosis and cell cycle arrest at the G₁/G₀phase in Colon 26 mouse colon cancer cells when used at concentrations of 20 and 16 µM, respectively.³

1.Xu, Z., Schenk, A., and Hertweck, C.Molecular analysis of the benastatin biosynthetic pathway and genetic engineering of altered fatty acid-polyketide hybridsJ. Am. Chem. Soc.129(18)6022-6030(2007) 2.Aoyagi, T., Aoyama, T., Kojima, F., et al.Benastatins A and B, new inhibitors of glutathione S-transferase, produced by Streptomyces sp. MI384-DF12. I. Taxonomy, production, isolation, physico-chemical properties and biological activitiesJ. Antibiot. (Tokyo)45(9)1385-1390(1992) 3.Kakizaki, I., Ookawa, K., Ishikawa, T., et al.Induction of apoptosis and cell cycle arrest in mouse colon 26 cells by benastatin AJpn. J. Cancer Res.91(11)1161-1168(2000)