YM-266183 and YM-266184, novel thiopeptide antibiotics produced by Bacillus cereus isolated from a marine sponge -: I.: Taxonomy, fermentation, isolation, physico-chemical properties and biological properties

Novel antibiotics, YM-266183 (1) and YM-266184 (2), were found in the culture broth of Bacillus cereus QN03323 which was isolated from. the marine sponge Halichondria japonica. The structures of both antibiotics were determined by several spectroscopic experiments as new thiopeptide compounds. They exhibited potent antibacterial activities against staphylococci and enterococci including multiple drug resistant strains, whereas they were inactive against Gram-negative bacteria.