Morinagadepsin

Identifier:  imarina:9216933

Handle: https://hdl.handle.net/20.500.11797/imarina9216933

Authors:  Harms, Karen; Surup, Frank; Stadler, Marc; Stchigel, Alberto Miguel; Marin-Felix, Yasmina

Abstract:
The new genus Morinagamyces is introduced herein to accommodate the fungus Api-osordaria vermicularis as inferred from a phylogenetic study based on sequences of the internal tran-scribed spacer region (ITS), the nuclear rDNA large subunit (LSU), and partial fragments of riboso-mal polymerase II subunit 2 (rpb2) and β‐tubulin (tub2) genes. Morinagamyces vermicularis was analyzed for the production of secondary metabolites, resulting in the isolation of a new depsipeptide named morinagadepsin (1), and the already known chaetone B (3). While the planar structure of 1 was elucidated by extensive 1D‐ and 2D‐NMR analysis and high‐resolution mass spectrometry, the absolute configuration of the building blocks Ala, Val, and Leu was determined as ‐L by Marfey’s method. The configuration of the 3‐hydroxy‐2‐methyldecanyl unit was assigned as 22R,23R by J‐ based configuration analysis and Mosher’s method after partial hydrolysis of the morinagadepsin to the linear derivative compound 2. Compound 1 showed cytotoxic activity against the mammalian cell lines KB3.1 and L929, but no antimicrobial activity against the fungi and bacteria tested was observed, while 2 was inactive. Compound 3 was weakly cytotoxic against the cell line L929, but did not show any antimicrobial activity.