Amycolapeptins A and B, Cyclic Nonadepsipeptides Produced by Combined-culture of Amycolatopsis sp. and Tsukamurella pulmonis

Two nonapeptide natural products, amycolapeptins A (1) and B (2) with a 22-membered cyclic depsipeptide skeleton, beta-hydroxytyrosine, and a highly modified side chain, which were not produced in a monoculture of the rare actinomycete Amycolatopsis sp. 26-4, were discovered in broth of its combined-culture with Tsukamurella pulmonis TP-B0596. The planar structures were elucidated by spectroscopic analyses (extensive 2D-NMR and MALDI-TOF MS/MS). The absolute configurations of component amino acids were unambiguously determined by the highly sensitive advanced Marfey's method we recently developed. Additionally, the structures of unstable/unusual moieties were corroborated by chemical synthesis and CD analysis.

Automated summary

Two nonapeptide natural products with a 22-membered cyclic depsipeptide skeleton, beta-hydroxytyrosine, and a highly modified side chain were discovered in a combined-culture of rare actinomycete Amycolatopsis sp. 26-4 with Tsukamurella pulmonis TP-B0596. The planar structures were elucidated through spectroscopic analyses, and the absolute configurations of component amino acids were determined using the advanced Marfey's method. Unstable/unusual moieties in the structures were corroborated by chemical synthesis and CD analysis.