药用蛞蝓抗菌肽基因的筛选鉴定与功能机制研究

The mechanisms of action that different from traditional antibiotics and difficult for bacteria to develop drug resistance, which have made anti-microbial peptides (AMPs) have great potential as new drugs against bacterial resistance. Chinese animal medicine Limax have a good anti-infection effect, which is recorded in Chinese pharmacopoeia such as the Great Dictionary of Chinese Medicine, but, there is no study on its antibacterial function and AMPs from it. Our study found that limax had antibacterial activity indeed, and peptide components with good antibacterial activity were isolated from limax. In this project, 1) The transcriptomes of three medical Limax species (Limax flavus, Philomycus bilineatus, and Agriolimax agrestis) will be sequenced by High-throughput sequencing technology, and the AMPs genes from Chinese animal medical Limax will be screened and identified comprehensively; 2) The antibacterial spectrum of the potential peptides will be determined, and the toxicity, stability, and induction of drug resistance of the peptides will be evaluated; 3) The potential in vivo antibacterial activity of the peptides will be evaluated by a mouse peritonitis model and a rat skin infection model. 4) The antibacterial mechanisms will be investigated. This research will excavate the AMPs from Chinese animal medicine Limax completely, and will be the first to reveal the function and mechanisms of AMPs from Chinese animal medicine Limax, which will actively promote the cognition and utilization of Chinese medical Limax resource and provide new candidates or molecular templates for the development of antibacterial drugs.

抗菌肽不同于传统抗生素的作用机制和不易诱导细菌产生耐药的特性，在应对细菌耐药新药的研发方面有很好的开发前景。《中药大辞典》等药典中记载蛞蝓有优良的抗感染疗效，但尚无蛞蝓抗菌功能及蛞蝓来源抗菌肽的研究。我们前期的研究证实蛞蝓具有抗菌功能，并获得具有良好抗菌活性的多肽组分。本项目在现有工作的基础上，1）通过对我国药用蛞蝓物种（黄蛞蝓、双线噬粘蛞蝓和野蛞蝓）进行高通量转录组测序研究，全面深入的筛选鉴定潜在抗菌肽基因；2）确定蛞蝓抗菌肽的抗菌谱，并评估其体内外毒性、稳定性及诱导耐药性情况；3）通过构建小鼠腹膜炎模型和大鼠皮肤感染模型等，检测蛞蝓抗菌肽的体内抗菌活性；4）探究解析蛞蝓抗菌肽的抗菌机制。开展本项目研究，将全面挖掘药用蛞蝓中的抗菌肽，并首次揭示药用蛞蝓抗菌肽的功能机制，从而推动药用蛞蝓资源的认识与利用，同时也为抗菌药物的研发提供新的候选分子或分子模板。

抗微生物肽在应对细菌耐药新药的研发方面有很好的开发前景，而动物类中药是发掘抗微生物多肽的良好资源。本项目针对具有抗微生物功效的中药蛞蝓资源开展转录组学研究，并基于转录组学及序列分析构建多肽序列资源库，从中获得大量抗微生物多肽/蛋白以及潜在抗微生物多肽序列。通过抗微生物活性研究，发掘出大量对口腔致病菌等具有良好活性且溶血活性低的多肽。这些活性多肽的发掘，为抗菌药物的研发提供了新的候选分子或分子模板。目前，在本项目的资助下已发表科研论文5篇，授权发明专利3项，另有3项发明专利处于实审公示。除此之外，本项目的其他相关研究正在开展中，已经获得了不错的研究结果。