基于组学技术的辣木籽肽MOp2对S.aureus的抑菌机制研究

辣木为云南特色优势植物资源，但一直存在蛋白生物学价值低的问题，如何提高蛋白质资源利用率是目前辣木产业发展面临的瓶颈。我们前期通过高效酶解、细胞膜色谱靶向筛选获得了抗金黄色葡萄球菌（S.aureus）活力强的高纯度辣木籽肽MOp2，但有关其结构、性质及作用机制尚不清楚。拟申请项目着眼于MOp2的结构解析及抑菌机制，通过结构鉴定、稳定性分析及溶血性、凝集性研究表征其分子特征和功能性质；采用转录组学和蛋白质组学技术分析MOp2对菌体壁膜形成、跨膜通道的影响，结合膜损伤作用阐释胞外机制；从基因和蛋白质水平研究MOp2对菌体遗传表达、基础物质与能量代谢及抗氧化能力的影响，以及可能的分子靶点，并结合凋亡诱导作用明确胞内机制，进一步探索辣木籽肽MOp2对S.aureus胞内外的双重作用机制，阐明其抑菌机理。研究可为新型天然食品防腐剂、功能性植物蛋白肽等高附加值辣木产品的研发提供理论依据。

Moringa oleifera is a characteristic and advantageous plant resource in Yunnan. However, there has always been a problem of low biological value of protein. How to improve the utilization rate of protein resources is the bottleneck of the development of Moringa oleifera industry at present. In the previous experiment, we obtained a highly purified Moringa oleifera seed derived peptide MOp2 with high activity against S.aureus by high-performance enzymatic hydrolysis and targeted screening by cell membrane chromatography, but the structure, properties and mechanism of action of MOp2 remain unclear. The proposed project intends to focus on the structural analysis and antibacterial mechanism of MOp2. First, the molecular characteristics and functional properties of MOp2 will be characterized by structural identification, stability analysis and hemolysis and agglutination studies. Second, the effects of MOp2 on bacterial cell wall and membrane formation and transmembrane channels will be analyzed by using transcriptomics and proteomics techniques, which combining with membrane damage can explain the extracellular mechanism of MOP2 against S.aureus. Third, the effects of MOp2 on bacterial genetic expression, metabolism of basic substances and energy and antioxidant capacity, and possible molecular targets will be studied at gene and protein levels, which combining with induction of apoptosis can explain the intracellular mechanism of MOP2 against S.aureus. The purpose based on the above research is to explore the dual mechanisms of intracellular and extracellular action of Moringa oleifera seed derived peptide MOp2 on S.aureus, and further clarify its antibacterial mechanism. The research can provide a theoretical basis for the research and development of high value-added Moringa oleifera products such as new natural food preservatives and functional vegetable protein peptides.