Fourteen-membered macrolides are a class of compounds with significant clinical value as antibacterial agents. As part of our ongoing investigation into the metabolites of sp. MST-91080, we report the discovery of resorculins A and B, unprecedented 3,5-dihydroxybenzoic acid (α-resorcylic acid)-containing 14-membered macrolides.
View Article and Find Full Text PDFAmycolatopsis sp. MST-135876 was isolated from soil collected from the riverbank of El Pont de Suert, Catalonia, Spain. Cultivation of MST-135876 on a range of media led to the discovery of a previously unreported dichlorinated cyclic hexapeptide, suertide A (D-Ser, 5-Cl-D-Trp, 6-Cl-D-Trp, L-Ile, D-Val, D-Glu), featuring an unprecedented pair of adjacent 5/6-chlorotryptophan residues.
View Article and Find Full Text PDFThe genus has been a rich source of bioactive natural products, medicinal chemicals, and novel drug leads for three-quarters of a century. Yet studies suggest that the genus is capable of making some 150,000 more bioactive compounds than all secondary metabolites reported to date. Researchers around the world continue to explore this enormous potential using a range of strategies including modification of culture conditions, bioinformatics and genome mining, heterologous expression, and other approaches to cryptic biosynthetic gene cluster activation.
View Article and Find Full Text PDFAspergillus burnettii is a new species belonging to the A. alliaceus clade in Aspergillus subgenus Circumdati section Flavi isolated from peanut-growing properties in southern Queensland, Australia. A.
View Article and Find Full Text PDFChemical investigation of a previously unreported indigenous Australian Streptomyces strain MST-91080 has identified six novel analogues related to the oxazole-pendanted macrodiolide, conglobatin. Phylogenetic analysis of the 16S rRNA gene sequence identified MST-91080 as a species of Streptomyces, distinct from reported conglobatin producer, Streptomyces conglobatus ATCC 31005. Conglobatins B-E diverge from conglobatin through differing patterns of methylation on the macrodiolide skeleton.
View Article and Find Full Text PDF1-Benzazepine is a pharmaceutically important scaffold but is rare among natural products. Nanangelenin A (), containing an unprecedented 3,4-dihydro-1-benzazepine-2,5-dione--prenyl--acetoxy-anthranilamide scaffold, was isolated from a novel species of Australian fungus, . Genomic and retrobiosynthetic analyses identified a putative nonribosomal peptide synthetase (NRPS) gene cluster ().
View Article and Find Full Text PDFChemical investigation of an undescribed Australian fungus, , led to the identification of the nanangenines - a family of seven new and three previously reported drimane sesquiterpenoids. The structures of the nanangenines were elucidated by detailed spectroscopic analysis supported by single crystal X-ray diffraction studies. The compounds were assayed for in vitro activity against bacteria, fungi, mammalian cells and plants.
View Article and Find Full Text PDFThe burnettramic acids are a new class of antibiotics from an Australian fungus Aspergillus burnettii. The rare bolaamphiphilic scaffold consists of β-d-mannose linked to a pyrrolizidinedione unit via a 26-carbon chain. The most abundant metabolite displayed potent in vitro antifungal activity.
View Article and Find Full Text PDFMacroalgae are a rich source of biologically active chemical diversity for pharmaceutical and agrichemical discovery. However, the ability to understand the complexities of their chemical diversity will dictate whether these natural products have a place in modern discovery paradigms. In this study, we examined the relationship between secondary metabolite production and biological activity for a cohort of 127 macroalgae samples collected from various locations across South Eastern Australia.
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