协同氟康唑抗耐药真菌的小分子探针设计合成及其靶点研究

Fungi become progressively resistant to conventional antifungal drugs and no better strategy is used to fight against it so far. In our previous work, we found that forsythiaside A, berberine, baicalein, and mangiferin could synergistically inhibit the resistant fungi with antifungal drugs, which might be a progressive method to fight against resistant fungi. Further research indicated they have same action mechanism,similar pharmacophore in SAR reaserch,besides their same efficacy. However, their action target remains unknown, which delay the further research for drug development. In this project, photoaffinity labeling probes will be employed to investigate their action targets, which might be the same target useful to overcome drug-resistance in fungi. The designed probes were consisted of three parts: drugs or ligands, triflouromethyl phenyl diazirine(for photoaffinity),and biotin(as a tag), which will be assembled by linkers. 30-50 probes will be designed and synthesized following by antifungal screening. 5-10 effective probes are expected to be obtained for the following photoaffinity labeling tests. The bioinformation of target proteins are expected to be obtained by inter or intra comparision of different kinds of probes.

真菌耐药日益严重，尚无良策。我们前期发现连翘酯苷A、小檗碱、黄芩素、芒果苷等化合物具有协同氟康唑抗耐药真菌作用。化合物之间具有相近的体内外药效、作用机制存相同之处；构效关系研究表明了它们有相似的药效基团。但我们对其作用靶点研究一直未获明确结果并严重制约研究的深入。本课题拟设计合成光亲和探针，探索上述化合物的作用靶点及其共同作用靶点的可能性，为抗耐药真菌药物研究提供新靶点。该类探针由药物或配体、三氟甲基苯基diazirine（光亲和部分）、生物素（作为标签）三部分组成。探针合成过程中，配合体外抗耐药真菌的活性跟踪，筛选30-50个探针，期望获得有效探针5-10个，用于光亲和结合靶点试验，获得相关蛋白的生物学信息。对获得的蛋白信息通过探针的类间比较、类内比较，最终获得靶点蛋白的生物学信息。

本课题基于小檗碱、连翘酯苷、黄芩素等天然产物能协同氟康唑抗耐药真菌的作用，通过结构优化，获得了系列新结构活性分子。通过构效关系研究，确定活性必需基团和非必需基团。据此，将光亲和基团（氮杂环丙烯）、炔基等功能基团引入非必需基团，设计合成具有靶点捕获作用的小分子探针20余个，通过体外活性筛选，获得活性探针10余个，用于耐药真菌蛋白结合试验，获得了差异条带，对差异条带进行高分辨质谱分析，提供了HSP90、ENO1等结合蛋白信息。目前正在对候选靶蛋白进行进一步鉴定。在基金支持下，发表SCI论文5篇，核心期刊论文3篇，授权专利1项，申请专利1项。培养研究生5名。