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Sansanmycins, members of the uridyl peptide antibiotics, are assembled by nonribosomal peptide synthetases (NRPSs), the substrate promiscuity of which results in the diversity of products. Further exploration of the NRPSs' substrate promiscuity by reinvestigating sansanmycin producer strain led to the isolation and structural elucidation of eight new uridyl peptides, sansanmycins H-O (1-8). Among them, sansanmycin L, containing a 6-OH-bicyclic residue and Phe3 first found at the position AA3, exhibited activity against M. tuberculosis H37Rv with an MIC value of 2 μg/mL, 8-fold more potent than that of the major compound, sansanmycin A (MIC = 16 μg/mL).

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Damming rivers addresses a range of society’s needs, but at the cost of fragmentation and other negative effects on freshwater ecosystems. This article examines hydropower development and fish conservation in the Upper Yangtze River Basin to explore strategies for managing dams more sustainably at the basin scale. We highlight the need to limit the effects of hydropower dams on freshwater biodiversity, and that protecting fish in reserves could be one of the most effective approaches to limiting the ecological effects of dams on fish. However, in the Yangtze River basin there are dams on the rivers in all but 1 of the 14 fish reserves mapped in this study, thus compromising the effectiveness of the reserves. In addition, the removal of some dams may not be as effective as suggested. Thus, we propose that limiting dam construction in protected tributaries is a ready-to-adopt conservation strategy. However, the adoption of this policy by the Chinese government will be determined by which of two competing policy changes (i.e. gradual or sudden) in the policy subsystem of dam construction will prevail. In this paper we illustrate how greater triage in the Upper Yangtze River Basin can deliver services to people and conserve freshwater biodiversity.