Dereplication Strategies for Targeted Isolation of New Antitrypanosomal Actinosporins A and B from a Marine Sponge Associated-Actinokineospora sp. EG49

Abstract

High resolution Fourier transform mass spectrometry (HRFTMS) and nuclear magnetic resonance (NMR) spectroscopy were employed as complementary metabolomic tools to dereplicate the chemical profile of the new and antitrypanosomally active sponge-associated bacterium Actinokineospora sp. EG49 extract. Principal Component (PCA), hierarchical clustering (HCA), and orthogonal partial least square-discriminant analysis (OPLS-DA) were used to evaluate the HRFTMS and NMR data of crude extracts from four different fermentation approaches. Statistical analysis identified the best culture one-strain-many-compounds (OSMAC) condition and extraction procedure, which was used for the isolation of novel bioactive metabolites. As a result, two new O-glycosylated angucyclines, named actinosporins A (1) and B (2), were isolated from the broth culture of Actinokineospora sp. strain EG49, which was cultivated from the Red Sea sponge Spheciospongia vagabunda. The structures of actinosporins A and B were determined by 1D- and 2D-NMR techniques, as well as high resolution tandem mass spectrometry. Testing for antiparasitic properties showed that actinosporin A exhibited activity against Trypanosoma brucei brucei with an IC50 value of 15 µM; however no activity was detected against Leishmania major and Plasmodium falciparum, therefore suggesting its selectivity against the parasite Trypanosoma brucei brucei; the causative agent of sleeping sickness.

Metabolomic Profiling and Genomic Study of a Marine Sponge-Associated Streptomyces sp.

“…These two complementary analytical techniques allow the rapid identification of classes of compounds present in the samples as well as the putative identification of specific compounds [20,21]. However, although LC-HRMS is extremely sensitive and can detect compounds present in very low quantities, there are certain classes of compounds that cannot be detected by the mass spectrometer, the reason being that they are unable to be ionized.…”

Production of Induced Secondary Metabolites by a Co-Culture of Sponge-Associated Actinomycetes, Actinokineospora sp. EG49 and Nocardiopsis sp. RV163

“…EG49 [20]. In this work, compounds 1 and 2 were confirmed to be the major metabolites present in this extract, and further attempts at the structure elucidation of minor metabolites were not made.…”

The synergistic effect of biosynthesized silver nanoparticles from a combined extract of parsley, corn silk, and gum arabic: in vivo antioxidant, anti-inflammatory and antimicrobial activities

“…Metabolomic profiling of P. crispum, S. maydis and a combination of the three crude extracts Metabolomic profiling was performed on the crude extracts of P. crispum, S. maydis and a combination of the three crude extracts to deliver general qualitative and quantitative profiles of metabolites that may be involved in the activity of the extracts [38]. Dereplication refers to the rapid identification of the known secondary metabolites and their quantification in crude unfractionated extracts [39,40]. Identification of metabolome was done on an Acquity Liquid Chromatography (LC) system coupled to a Synapt G2 HDMS quadrupole time-offlight hybrid mass spectrometer (Waters, Milford, USA).…”