Systematic UPLC-ESI-MS/MS study on the occurrence of staurosporine and derivatives in associated marine microorganisms from Eudistoma vannamei

Abstract

O estudo fitoquímico do invertebrado marinho Eudistoma vannamei levou ao isolamento de derivados do alcalóide estaurosporina, que apresentaram uma potente atividade citotóxica contra linhagens de células humanas de câncer. A ocorrência destes alcalóides pode ser correlacionada a presença de microorganismos associados ao animal, como por exemplo bactérias do gênero Streptomyces. Visando confirmar essa hipótese, precedeu-se o isolamento e cultivo dos microrganismos associados com E. vannamei (84 cepas isoladas). Estudos sistemáticos das reações de fragmentação da estaurosporina e derivados, apoiados pela química computacional, permitiram definir os principais padrões de fragmentação. Esses padrões foram utilizados em análises exploratórias por LC-MS/MS visando pesquisar a presença de derivados de estaurosporinas nos microrganismos isolados. Esse procedimento permitiu identificar estaurosporina em uma espécie de Streptomyces, contudo não com o mesmo padrão de oxidação da molécula ativa isolada no extrato da Ascídia. Finalmente, o extrato dessa cepa mostrou também significativa atividade citotóxica contra linhagens de câncer.Former bioactivity-guided analysis of the marine invertebrate Eudistoma vannamei led to the isolation of staurosporine derivatives, which revealed strong cytotoxic activity against several human cancer cell lines. The occurrence of such alkaloids in E. vannamei may be correlated to the presence of associated biota, such as Streptomyces bacteria. In agreement to this hypothesis, marine microorganisms associated with E. vannamei were recovered and cultured, leading to a total of 84 isolated bacterial strains. Gas phase fragmentation reactions of staurosporine and derivatives were systematically studied and the analyzed results further supported by computational chemistry studies. The resulting fragment patterns were used to search for the presence of different derivatives in extracts of isolated microorganisms, thereby using LC-MS/MS analysis in MRM mode. These results evidenced that one isolated Streptomyces sp. was able to generate staurosporine, while none of the hydroxy-7-oxo derivatives were detected. Finally, significant cytotoxic activity against human cancer lines was observed for one of the extracts.

Prospecting Anticancer Compounds in Actinomycetes Recovered from the Sediments of Saint Peter and Saint Paul's Archipelago, Brazil

“…S8, Supporting information), can be justified by the presence of a OH group in the polyaromatic nucleus. A mechanism proposal for these fragments was previously published by Andreo and coworkers . The MS/MS of rifamycin B produced the ions at m / z 696.2554 and 724.2808 (Fig.…”

Metabolite profile of marine-derived endophytic Streptomyces sundarbansensis WR1L1S8 by liquid chromatography-mass spectrometry and evaluation of culture conditions on antibacterial activity and mycelial growth

“…; Andreo et al . ) carried out directly on the crude extracts obtained under various culture conditions. By injecting the pure metabolites previously characterized (Djinni et al .…”

Gas‐phase fragmentation of protonated piplartine and its fungal metabolites using tandem mass spectrometry and computational chemistry

“…Computational quantum calculations provide the information required to identify the ionization sites and the stability of each ionic species formed during the fragmentation in MS/MS experiments . Thus, the combination of MS/MS with computational chemistry provides valuable information for understanding gas‐phase fragmentation and to support the characterization of organic compounds in general …”

“…[23] Soft ionization sources, such as electrospray ionization (ESI) [24] and matrix-assisted laser desorption/ionization (MALDI) [25] coupled with tandem mass spectrometry (MS/MS) analysis, have contributed to the characterization and elucidation of metabolite structures in complex matrices. [26][27][28] The fragmentation pathways of organic compounds are also important for characterization and structural elucidation of substances in metabolomic studies. [29] Computational quantum calculations provide the information required to identify the ionization sites and the stability of each ionic species formed during the fragmentation in MS/MS experiments.…”

“…[30][31][32] Thus, the combination of MS/MS with computational chemistry provides valuable information for understanding gas-phase fragmentation and to support the characterization of organic compounds in general. [28,33,34] Due to the remarkable biological activities of piplartine, (1, Fig. 1), we studied its gas-phase fragmentation as well as that of two of its hydrogenated metabolites obtained by P. crustosum VR4 biotransformation (compounds 2 and 3, Fig.…”