基于反义干扰肽核酸模板的抗菌肽自组装及其抗菌机理研究

Being the new generation of drug candidate against antimicrobial infection, antimicrobial peptides still suffer from the bottlenecks of low biological activity and potential drug resistance in clinic due to their simplex antimicrobial mechanism. Cell penetrating peptide (CPP) modified peptide nucleic acid (PNA), functioning as an antisense gene drug, could effectively interfere the transcription or translation level of the target gene. Based on the preliminary results of antimicrobial peptides and PNA based protein self assembly, we herein propose to develop a PNA based antimicrobial complex using antimicrobial peptides with different mechanisms as building blocks. This complex combined three antimicrobial mechanism: spontaneously disturbing the membrane structure, inhibiting the in vivo protein expression and interfering the biological pathway. Therefore, it is supposed to dramatically increase the antimicrobial activity and prevent microbial to generate resistance,. Owing to its advantages of precision, controllable and good bio-compatibility, this self-assembly platform would find its profound application in new drug combinational design and drug delivery.

抗菌肽是新一代抗微生物感染的潜在药物前体。单一的抗菌机理使抗菌肽在临床应用上具有活性低和潜在耐药性等技术瓶颈。肽核酸（PNA）作为反义核酸诊疗试剂，经过跨膜肽修饰后可有效地干扰体内靶向基因的转录或翻译水平。在针对抗菌肽以及基于PNA的蛋白自组装的研究基础上，本课题将利用PNA为组装模板、具有不同抗菌机理的抗菌肽为组装元件，探索和研制具有多重抗菌机理及显著抗菌活性的抗菌复合物。该复合物将复合三种抗菌机理，即对微生物细胞膜的破坏、对微生物体内重要蛋白表达的抑制以及对微生物体内重要信号通路的抑制，降低微生物发展抗药性的可能。同时，这一组装平台还具有精确、可控、生物兼容等诸多优点，在新药组合及药物传递领域有广阔应用前景。

抗菌肽是新一代抗微生物感染的潜在药物前体。单一的抗菌机理使抗菌肽在临床应用上具有活性低和潜在耐药性等技术瓶颈。肽核酸（PNA）作为反义核酸诊疗试剂，经过跨膜肽修饰后可有效地干扰体内靶向基因的转录或翻译水平。在针对抗菌肽以及基于PNA的蛋白自组装的研究基础上，本课题将利用PNA为组装模板、具有不同抗菌机理的抗菌肽为组装元件，探索和研制具有多重抗菌机理及显著抗菌活性的抗菌复合物。本项目按照研究计划，我们开发了一种新型的肽核酸介导的蛋白精准自组装方法，并对机理进行了初步探索；此外，我们选择AM-22作为合成前体，进行结构上的简化，集中体现在将β折叠两段的氨基酸进行逐渐删除，以获得分子量更小的候选抗菌肽。接下来，进行了AM-22对抗白色念珠菌的筛选实验以及细胞毒性评价实验；第三，将抗菌肽与纳米粒子偶联，实现了皮肤感染的修复；第四，开发了自组装检测新方法。本项目研究成果在新药组合及药物传递领域有广阔应用前景。