CYST WALL ENDOPROTEASES OF ENTAMOEBA INVADENS AND ENTAMOEBA HISTOLYTICA

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 入侵内阿米巴和溶组织内阿米巴是相关的肠道病原菌。前者是影响几个爬行动物分类群的病原体，后者是人类的病原体。雅各布蛋白是入侵乳杆菌囊壁的丰富成分，其同源物存在于溶组织乳杆菌中。雅各布蛋白具有保守的凝集素样结构域，可能对维持这些病原体的囊壁完整性很重要。内阿米巴的内切酶位点在序列上是保守的，因此蛋白降解事件对于囊壁的正常功能可能是重要的。溶组棘球藻基因组中的大多数蛋白酶是半胱氨酸蛋白酶，这表明可能的Jacob蛋白酶是这种类型的。含有推测的内阿米巴蛋白酶位点的FITC标记肽已经被构建用于使用包括MALDI-TOF质谱分析在内的方法检测蛋白酶活性的策略。本研究试图通过使用已知的蛋白酶抑制剂的策略来鉴定溶组织埃希菌细胞提取物中的特定蛋白酶活性。结果表明，将使用特定的抑制剂来亲和富集酶，并将使用蛋白质组学的方法来鉴定具有活性的蛋白酶(S)。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Entamoeba invadens and Entamoeba histolytica are related enteric pathogens. The former is a pathogen affecting several reptile taxons and the later is a pathogen in man. Jacob proteins are abundant components of the cyst wall in E. invadens and homologues of it exist in E. histolytica. The Jacob proteins have conserved lectin-like domains and are likely important for maintenance of cyst wall integrity in these pathogens. Putative endoprotease sites are conserved in their sequence across Entamoeba species and therefore a proteolytic event may be important for proper function of the cyst wall. That most proteases in the E. histolytica genome are cysteine proteases suggests that the putative Jacob proteases are of this type. FITC label peptides containing the putative Entamoeba protease sites have been constructed for use in strategies to detect protease activity using approaches including MALDI-TOF mass spectrometric analysis. This study attempts to identify specific protease activities in E. histolytica cell extracts in strategies using known protease inhibitors. As results indicate, specific inhibitors will be used for affinity enrichment of the proteases and proteomics approaches will be used to identify the active protease(s).