For exploring structurally diverse metabolites and uniquely metabolic mechanisms, we systematically investigated the chemical constituents and putative biosynthesis of Janibacter sp. SCSIO 52865 derived from the deep-sea sediment based on the OSMAC strategy, molecular networking tool, in combination with bioinformatic analysis. As a result, one new diketopiperazine (1), along with seven known cyclodipeptides (2-8), trans-cinnamic acid (9), N-phenethylacetamide (10) and five fatty acids (11-15), was isolated from the ethyl acetate extract of SCSIO 52865. Their structures were elucidated by a combination of comprehensive spectroscopic analyses, Marfey's method and GC-MS analysis. Furthermore, the analysis of molecular networking revealed the presence of cyclodipeptides, and compound 1 was produced only under mBHI fermentation condition. Moreover, bioinformatic analysis suggested that compound 1 was closely related to four genes, namely jatA-D, encoding core non-ribosomal peptide synthetase and acetyltransferase.
Keywords: Janibacter sp. SCSIO 52865; bioinformatic analysis; cyclodipeptides; metabolites; structural elucidation.