Theonellamide G, a Potent Antifungal and Cytotoxic Bicyclic Glycopeptide from the Red Sea Marine Sponge Theonella swinhoei
نویسندگان
چکیده
In our search for bioactive metabolites from marine organisms, we have investigated the polar fraction of the organic extract of the Red Sea sponge Theonella swinhoei. Successive chromatographic separations and final HPLC purification of the potent antifungal fraction afforded a new bicyclic glycopeptide, theonellamide G. The structure of the peptide was determined using extensive 1D and 2D NMR and high-resolution mass spectral determinations. The absolute configuration of theonellamide G was determined by chemical degradation and 2D NMR spectroscopy. Theonellamide G showed potent antifungal activity towards wild and amphotericin B-resistant strains of Candida albicans with IC₅₀ of 4.49 and 2.0 μM, respectively. Additionally, it displayed cytotoxic activity against the human colon adenocarcinoma cell line (HCT-16) with IC₅₀ of 6.0 μM. These findings provide further insight into the chemical diversity and biological activities of this class of compounds.
منابع مشابه
Draft Genome Sequence of “Candidatus Synechococcus spongiarum” m9, Binned from a Metagenome of South China Sea Sponge Theonella swinhoei
"Candidatus Synechococcus spongiarum" represents the widespread cyanobacterial symbionts found in marine sponges with relatively high genomic variability and likely important ecological roles. We present here the draft genome sequence of "Candidatus Synechococcus spongiarum" m9, which was assembled from a metagenome of Theonella swinhoei sampled in the South China Sea.
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