Thielavins W-Z₇, New Antifouling Thielavins from the Marine-Derived Fungus Thielavia sp. UST030930-004.

Eleven new depsides-thielavins W-Z (-) and thielavins Z₁-Z₇ (-)-and also four known thielavins-A, H, J, and K (-)-were isolated from the ethyl acetate extract of a marine-derived fungal strain sp UST030930-004. All of these compounds were evaluated for antifouling activity against cyprids of the barnacle (=) . The results showed that compounds 1-3 and 6-13 were active, with EC values ranging from 2.

Caspase-3-dependent apoptosis of citreamicin ε-induced HeLa cells is associated with reactive oxygen species generation.

Citreamicins, members of the polycyclic xanthone family, are promising antitumor agents that are produced by Streptomyces species. Two diastereomers, citreamicin ε A (1) and B (2), were isolated from a marine-derived Streptomyces species. The relative configurations of these two diastereomers were determined using NMR spectroscopy and successful crystallization of citreamicin ε A (1).

Four new antibacterial xanthones from the marine-derived actinomycetes Streptomyces caelestis.

Four new polycyclic antibiotics, citreamicin θ A (1), citreamicin θ B (2), citreaglycon A (3), and dehydrocitreaglycon A (4), were isolated from marine-derived Streptomyces caelestis. The structures of these compounds were elucidated by 1D and 2D NMR spectra. All four compounds displayed antibacterial activity against Staphylococcus haemolyticus, Staphylococcus aureus, and Bacillus subtillis.

NMR studies on binding sites and aggregation-disassociation of fluorinated surfactant sodium perfluorooctanoate on protein ubiquitin.

The fluorinated surfactant sodium perfluorooctanoate (SPFO) could bind onto ubiquitin (UBQ) and induce the unfolding of UBQ. By using (15)N-edited heteronuclear single-quantum coherence (HSQC) NMR and (19)F NMR to monitor (15)N-labeled UBQ and SPFO, respectively, the binding sites and the aggregation process of SPFO on UBQ at various SPFO concentrations were observed. A detailed process from specific binding to cooperative binding of SPFO on UBQ, and a detailed structure change of UBQ upon the increase of SPFO concentration were obtained.