Trichostatins are potent inhibitors of histone deacetylase (HDAC). In this work, a new trichostatin derivative isotrichostatin RK (1) and five known compounds trichostatin RK (2), JBIR-111 (3), 9179B (4), trichostatic acid (5) and trichostatin A (6) were isolated from marine-derived Streptomyces sp. SCSIO 40028. The biosynthetic gene cluster (tsnB) for trichostatins was identified from Streptomyces sp. SCSIO 40028 and validated by heterologous expression in Streptomyces lividans TK64. N-Methyltransferase TsnB8 was demonstrated to catalyze successive methyltransfer reactions by in vivo gene inactivation and in vitro enzyme assays.
