家蝇Phormicin蛋白表达及对白色念珠菌的抑菌活性分析

Expression and Inhibiting Activity Analysis of Housefly Phormicin Protein to Candida albicans

防御素是一类具有广普抗菌活性的阳离子抗菌肽,而家蝇(Musca domestica)的Phormicin属于防御素超家族。白色念珠菌(Candida albicans)是临床上常见的引起人体感染的条件致病真菌。随着免疫缺陷病、糖尿病等疾病发生率的增加,在病人体内植入设备的白色念珠菌残留及附带感染日益成为临床感染的常见类型。本研究制备了家蝇Phormicin A、Phormicin B的原核表达蛋白,将其作用于白色念珠菌。微量液体稀释法测定了其最小抑菌浓度为2.5mmol/L和1.875mmol/L。进一步绘制了其对白色念珠菌的时间杀菌曲线。结果显示,二者对白色念珠菌都具有一定的抑菌效果。本研究为进一步探索Phormicin参与家蝇天然免疫和揭示家蝇抗真菌防御中的机制提供理论参考,为开发多肽类抗真菌药物提供线索。

Defensin is a kind of cationic antimicrobial peptides with broad antibacterial activity. Phormicin of housefly belongs to this defensin superfamily. Candida albicans is a common conditioned pathogenic fungus that causes human infection. The residual and incidental infection of C. albicans implanted in patients has become a common type of clinical infection as the incidence of diseases such as immunodeficiency and diabetes increases in recent years. In this study, prokaryotic expression proteins of Musca domestica Phormicin A and B were prepared and applied to Candida albicans. The minimum inhibitory concentrations(MIC) were 2.5 mmol/L and 1.875 mmol/L. Further, the time sterilization curve of C. albicans was drawn. These results showed that both of them had certain inhibition effect on C. albicans. This study provided a theoretical reference for further exploring and uncovered the mechanism of Phormicin participating in innate immunity and fungal defense of housefly. And it also provided clues for developing polypeptide antifungal drugs.