海洋来源真菌抗肿瘤活性产物的深入挖掘

In our previous work, some marine-derived Actinomycetes without antitumor activities were used as initial strain to explore their silent metabolites using DES mutation, neomycin and streptomycin-resistant screening. Recently, DMSO-mediated DES mutation had been first applied to obtain antitumor mutants from a marine-derived fungus (Penicillium purpurogenum G59) without antitumor activities, and a series of newly produced metabolites (including lots of new structures) had been isolated from some active mutants. Based on the above mentioned results, we want to undertake two main works as follows: 1) A series of antitumor mutants had been obtained from the initial strain Penicillium purpurogenum G59 by DMSO-mediated neomycin-resistant screening, and two antitumor mutants will be chosen for exploring their newly produced metabolites. This work will improve the technique of activating the silent metabolites of fungi, which was established by our group for the first time. 2) Expanded the initial strain from inactive fungal strain to active fungal strain to explore the potential of activating silent metabolites of the above mentioned technique (DMSO-mediated DES mutation and DMSO-mediated neomycin-resistant screening). And some mutants will be chosen for newly produced metabolites research. The carrying out of the project will further improved the technique for activating silent pathway to elicit the metabolic potentials of microbial isolates, and will improve the utilization of the talent strain.

课题组前期开展了放线菌的硫酸二乙酯诱变、新霉素及链霉素的抗性筛选及其突变株新产次级代谢产物的研究。近年，课题组以海洋来源无抗肿瘤活性的产紫青霉G59为出发菌株首次对真菌开展了DMSO介导的硫酸二乙酯诱变，获得了数十株具有良好抗肿瘤活性的突变株，并从突变株中得到了包括一系列新结构化合物在内的新产次级代谢产物。在此基础上本课题拟主要开展以下两方面工作：1）针对课题组最近获得的产紫青霉G59的新霉素抗性突变株开展其新产活性次级代谢产物的研究，进一步完善课题组所建立的激活沉真菌默次级代谢产物的技术方法。2）拓展课题组所建立的激活沉默次级代谢产物的技术方法的施用对象由无活性真菌至活性真菌，进一步探索该方法改造真菌次级代谢功能以获取多样化次级代谢产物的能力，并从突变株中分离得到多样化的新产活性次级代谢产物。通过本课题的实施可以进一步完善激活沉默次级代谢产物的新技术方法，提高海洋真菌优质资源的利用效率。

课题组前期开展了放线菌的硫酸二乙酯诱变、新霉素及链霉素的抗性筛选及其突变株新产次级代谢产物的研究。近年，课题组以海洋来源无抗肿瘤活性的产紫青霉G59为出发菌株首次对真菌开展了DMSO介导的硫酸二乙酯诱变，获得了数十株具有良好抗肿瘤活性的突变株，并从部分突变株中得到了包括一系列新结构化合物在内的新产次级代谢产物。在此基础上本课题主要完成了以下几个方面工作：1）完成了两株新霉素抗性突变株的新霉素抗性导入验证工作，并从上述两株突变株中分离得到新产次级代谢产物31个，其中新结构化合物7个；2）分离富集抗肿瘤活性化合物 Penicimutanolones未拆分混合物3.5 克；采用手性色谱柱法进行拆分，得到Penicimutanolone A 2.2克，Penicimutanolone B 0.7克;采用14种人癌细胞系统评价了上述两个化合物的体外抗肿瘤活性，采用小鼠 S180 细胞移植瘤模型评价了Penicimutanolone A的体内抗肿瘤活性；3）完成了一株极地深海来源真菌S-3-25的发酵产物研究，从中得到化合物20个；采用硫酸二乙酯诱变及新霉素抗性筛选等手段，以真菌S-3-25为原始菌获得突变株90余株；从其中一株突变株中分离得到新产次级代谢产物37个，其中5个为新结构化合物。该课题通过两株新霉素抗性突变株抗性导入验证实验及其新产次级代谢产物研究，完善了课题组所建立的激活沉默次级代谢产物的技术方法。该课题拓展课题组所建立的激活沉默次级代谢产物的技术方法的施用对象由无活性真菌至活性真菌，并取得成功，进一步说明课题组所建立的激活沉默次级代谢产物的新技术方法具有普适性，可用于提高海洋真菌优质资源的利用效率。