单核细胞增多性李斯特菌(LM)是人兽共患李斯特菌病的病原体，被WHO列为的4大食源性致病菌之一。已有研究表明一些基于SrtA分选的表面蛋白在LM的致病中发挥重要作用，但是目前尚没有基于SrtA分选表面蛋白谱的系统研究。本实验室从临床绵羊脑炎病例中分离到的一株LM，命名为LM90株。本研究首先利用同源重组技术构建LM90株srtA基因缺失株，利用蛋白组学技术鉴定LM90野生株和srtA缺失株的细胞壁差异蛋白，通过差异蛋白的鉴定和筛选，生物信息学分析差异蛋白的基序、结构和功能，获得基于SrtA的分选蛋白谱及新的表面蛋白；同时结合免疫学技术对细胞壁蛋白进行反应原性的鉴定、筛选，获得具有抗原性的新表面蛋白；对筛选蛋白构建其缺失株，研究其在细胞粘附与侵袭，小鼠毒力试验等生物学特性中的作用，以期发现新的毒力因子，为进一步了解单核细胞增多性李斯特菌的免疫、致病机制以及筛选药物靶点提供科学依据。

Listeria monocytogenes(LM) is a zoonoses listeriosis pathogen and is identified with one of four most important food-borne disease pathogens by WHO.Studies showed that some surface proteins sorted by SrtA play a important role in LM pathogenesis ,but there has been no systematic analysis to identify the major cell wall-associated proteins profile. In our previous study, a LM isolate named LM90 was identified from clinical sheep encephalitis case. In this research, first, to construct srtA deletion mutant with homologous recombination. Second,to establish cell wall-associated proteins profile and to screen new antigenic proteins from cell wall proteins based on SortA in LM90 using proteomics and immuno proteomics approach. Third, to confirmed selected protein's role in cell adhesion and invasion, mouse virulence and other biological characteristics. The achievement of this research can provide a scientific basis for further understanding immune and pathogenic mechanism of LM and for screening drug targets of LM.