Integrated Omics-Based Discovery of Bioactive Halogenated Metabolites from the Deep-Sea sp. B188M101.

Using the one-strain-many-compounds (OSMAC) culturing approach, metabolomic studies, and bioassay-guided purification, we have isolated and characterised three new chlorinated natural products, agelolines B-D (-), together with two known compounds, ageloline A () and gausemycin A (), which have been identified by high-resolution mass spectrometry and 1D and 2D NMR analyses. The preliminary evaluation of three small-scale extracts (M400, R358 and SGG) against the fish pathogen, subsp. KELDUR265-87, showed that the R358 extract displayed significant activity. Furthermore, the natural products (-) were evaluated against the fish pathogen and human pathogens ( L2125, ATCC6538P, and L44) using a serial dilution assay. Compound displayed activity against ATCC6538P, L2125, and L44 with MIC values of 6, 32, and 64 µg/mL, respectively. Interestingly, only gausemycin A () exhibited considerable inhibition against with an MIC value of 32 µg/mL, and the activity increased by two-fold when supplemented with 0.45 mM calcium salt, while and showed moderate inhibition against L2125. The biosynthetic pathways of compounds - were proposed. This is the first report of specific inhibition of by .