Macrolactin W, a new antibacterial macrolide from a marine Bacillus sp.

Bioactivity-guided isolation for the new/novel metabolites from the EtOAc extract obtained from the culture broth of a marine Bacillus sp. 09ID194 followed by chromatographic fractionations and subsequently HPLC purifications led to the isolation of two known macrolides, macrolactins A (1) and Q (2), together with a new glycosylated marcrolide, macrolactin W (3). The chemical structures of compounds 1–3 were assigned based on extensive MS and NMR spectral data analysis and literature review. Compound 3 showed potent antibacterial activity against both Gram-positive and Gram-negative pathogenic bacteria.

Graphical abstractMacrolactin W (3), a new potent antibacterial macrolide, was isolated from a marine Bacillus sp. together with two known macrolactins A (1) and Q (2) through bioassay-guided isolation. The structure of this new macrolactin was determined by extensive MS, 1D and 2D NMR spectral data analysis. Macrolactin W is the first macrolactin where succinic acid moiety was fully esterified.Figure optionsDownload full-size imageDownload as PowerPoint slide