Burnettramic acid A and its aglycone are members of 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. Burnettramic acid A is active against the Gram positive bacteria, B. subtilis and S. aureus, with IC50 2.3 and 5.9 µg/mL, respectively. Burnettramic acid A is a potent antifungal agent (IC50 0.5 µg/mL and 0.2 µg/mL against C. albicans and S. cerevisiae, respectively). Burnettramic acid A is also active against murine myeloma NS-1 cell line (IC50 13.8 µg/mL). Removal of the glycosyl group negates antibiotic and antifungal activity, but not activity against murine myeloma cell line (IC50 8.5 µg/mL for the aglycone).
Molecular Formula | C35H61NO7 |
References |
Gilchrist C et al (2020) Comprehensive chemotaxonomic and genomic profiling of a biosynthetically talented Australian fungus, Aspergillus burnettii sp. nov. FG & B 143:103435 Hang et al (2019) Discovery and heterologous biosynthesis of the burnettramic acids: Rare PKS-NRPS-Derived bolaamphiphilic pyrrolizidinediones from an Australian Fungus, Aspergillus burnettii. Org Lett 21:1287 |