Sobreira Aline C M, Pinto Francisco das Chagas L, Florêncio Katharine G D, Wilke Diego V, Staats Charley C, Streit Rodrigo de A S, Freire Francisco das Chagas de O, Pessoa Otília D L, Trindade-Silva Amaro E, Canuto Kirley M
Departamento de Química Orgânica e Inorgânica, Universidade Federal do Ceará Fortaleza Brazil.
Núcleo de Pesquisa e Desenvolvimento de Medicamentos, Universidade Federal do Ceará Fortaleza Brazil
RSC Adv. 2018 Oct 17;8(62):35575-35586. doi: 10.1039/c8ra06824k. eCollection 2018 Oct 15.
In the present study, we integrated liquid chromatography high-resolution mass spectrometry (LC-HRMS) and high-throughput DNA sequencing for prospecting cytotoxic specialized metabolites from , an endophytic fungus associated to the medicinal plant . LC-HRMS profiling allowed identifying putatively eleven compounds in the ethyl acetate extract from broth. Additionally, a chemical fractionation guided by cytotoxicity combined with spectrometric analysis resulted in the isolation of three compounds: the cyclopeptide cyclo-l-Phe-d-Leu-l-Leu-l-Leu-l-lle along with the known rotenoids rotenolone and tephrosin. MTT assay showed that tephrosin (IC 0.51 μg mL) has strong cytotoxic effect and may be pointed out as the compound responsible for the antiproliferative activity of . Next Generation Sequencing (NGS) and genome mining of draft genome revealed 56 contigs codifying specialized metabolites biosynthesis-related enzymes. Nearly half of such genes (44.6%) could be mapped to orphan Biosynthetic Gene Clusters (BGCs) of related plant pathogens belonging to family Botryosphaeriaceae. Also, screening for rotenoids biosynthetic enzymes led to characterization of a putative chalcone isomerase-like (CHI-like) protein. This is the first report of rotenoids biosynthesized by a fungus, unveiling a unique ability of .
在本研究中，我们整合了液相色谱高分辨率质谱（LC-HRMS）和高通量DNA测序技术，以探寻与药用植物相关的内生真菌产生的细胞毒性特殊代谢产物。LC-HRMS分析能够在该真菌培养液的乙酸乙酯提取物中鉴定出11种推定化合物。此外，通过细胞毒性指导的化学分级分离结合光谱分析，分离出了3种化合物：环肽环-1-苯丙氨酸-d-亮氨酸-1-亮氨酸-1-亮氨酸-1-异亮氨酸，以及已知的鱼藤酮类化合物鱼藤酮醇和灰叶素。MTT分析表明，灰叶素（IC 0.51μg/mL）具有很强的细胞毒性作用，可能是该真菌具有抗增殖活性的化合物。对该真菌基因组草图进行的新一代测序（NGS）和基因组挖掘揭示了56个编码特殊代谢产物生物合成相关酶的重叠群。近一半的此类基因（44.6%）可映射到葡萄座腔菌科相关植物病原体的孤儿生物合成基因簇（BGCs）。此外，对鱼藤酮类生物合成酶的筛选导致了一种推定的查尔酮异构酶样（CHI样）蛋白的表征。这是关于真菌生物合成鱼藤酮类化合物的首次报道，揭示了该真菌的独特能力。
