Jiang, Zhong-Ke, Hu, Xin-Xin, Xiao, Lan-Lin, Ren, Yi-Ru, Shakhtina, Anna N., Lukianov, Dmitrii A., Osterman, Ilya A., Sergiev, Petr V., Dontsova, Olga A., Wang, Hao, Wu, Gang, You, Xue-Fu, and Sun, Cheng-Hang
One new virginiamycin derivative, 'beilunmycin' (1), and three known virginiamycin antibiotics, 16-hydroxy-virginiamycin M1 (2), virginiamycin M2 (3), and virginiamycin M1 (4), were isolated from the culture of a mangrove-derived endophytic Streptomyces sp. 2BBP-J2. The structures were characterized on the basis of their spectroscopic data, and the absolute configuration of 1 was established by ECD calculations. Compounds 1–4 exhibited antibacterial activities against Gram-positive bacteria, with MIC values in the range of 0.5–16 μg/ml. All the compounds demonstrated strong protein translation-stalling activity, with minimal concentrations detected with pDualrep2 in the range of 1.9–5.9 nmol. [ABSTRACT FROM AUTHOR]