Identification of Obscurolide-Type Metabolites and Antifungal Metabolites from the Termite-Associated Streptomyces neopeptinius BYF101

Abstract

Streptomyces spp. are well-known symbiotic microorganisms that produce antimicrobial metabolites against various pathogens. We isolated actinomycetes from the body surface of the termite Odontotermes formosanus and identified it as Streptomyces neopeptinius BYF101 based on 16S rRNA phylogenetic analysis. Chemical analysis of the cultures of termite-associated S. neopeptinius BYF101 via HR-MS2 and GNPS analyses enabled the isolation and identification of 20 metabolites, including the unreported obscurolide-type metabolites (1–3). The chemical structures of unreported compounds (1–3) were elucidated using HR-ESI-MS and 1D and 2D NMR analysis, and their absolute configurations were determined via chemical reactions followed by the application of competing enantioselective acylation (CEA) and computational methods for ECD and DP4+ probability calculation. The isolated compounds (1–20) were tested to determine their antifungal activity against two human fungal pathogens, Candida albicans and Cryptococcus neoformans. Among the compounds tested, indole-3-carboxylic acid (9) displayed antifungal activity against C. neoformans, with an MIC value of 12 μg/mL.

Serratiomycins D1–D3, Antibacterial Cyclic Peptides from a Serratia sp. and Structure Revision of Serratiomycin

“…Recently, 20 metabolites, including three previously unreported obscurolide-type metabolites, were isolated from Streptomyces neopeptinius , which was obtained from the surface of the termite Odontotermes formasanus . Among these 20 metabolites, indole-3-carboxylic acid exhibited antifungal activity against C. neoformans . These findings collectively emphasize the importance of insect-microbiome-derived metabolites, which provide structural diversity and serve as promising chemical sources for the development of pharmaceutical compounds.…”

On the way to potential antifungal compounds: synthesis and in vitro activity of 2-benzofuranylacetic acid amides

“…In this context, remarkable progress is being made in the development of new bioactive compounds against phytopathogens such as FOX on a weekly basis. [10][11][12][13][14][15][16][17][18] However, many of these advancements come with a signicant drawback. Most active compounds are derived from natural sources, resulting in limited quantities that make it challenging to conduct thorough testing and eld evaluations.…”