Natalamycin A, an ansamycin from a termite-associated Streptomyces sp
(2014) Natalamycin A, an ansamycin from a termite-associated Streptomyces sp Chem. Sci. 5(11), 4333-4338.
We report a preliminary functional and complete structural characterization of a highly unusual geldanamycin analog, natalamycin A, that was isolated from Streptomyces strain M56 recovered from a South African nest of Macrotermes natalensis termites. Bioassay-guided fractionation based on antifungal activity led to the isolation of natalamycin A, and a combination of NMR spectroscopy and X-ray crystallographic analysis, including highly-accurate quantum-chemical NMR calculations on the largest and most conformationally-flexible system to date, revealed natalamycin A's three-dimensional solid- and solution-state structure. This structure along with the structures of related compounds isolated from the same source suggest a geldanamycin-like biosynthetic pathway with unusual post-PKS modifications.
doi: 10.1039/C4SC01136H PMID: 25386334