Comprehensive Proteomic Analysis of Trypanosoma cruzi Epimastigote Cell Surface Proteins by Two Complementary Methods

Trypanosoma cruzi is a protozoan that causes Chagas’ disease, a neglected infectious illness that affects millions of people, mostly in Latin America. Here, the cell surface subproteome of the T. cruzi epimastigote life form was characterized. In order to prepare samples enriched in epimastigote plasma membrane protein, two distinct methodologies were optimized and evaluated. The first methodology was based on cell surface trypsinization (Shave) of intact living cells while the second approach used biotinylation of cell surface proteins followed by streptavidin affinity chromatography isolation of the labeled proteins. Both T. cruzi subproteomes were analyzed by LC-MS/MS. The results showed that the methodologies offered comprehensive and complementary information about the parasite’s plasma membrane subproteome.

克氏锥虫（Trypanosoma cruzi）是一种原生动物，可引发恰加斯病（Chagas’ disease）——一种波及数百万人群的被忽视传染病，其流行区域主要集中于拉丁美洲。本研究对克氏锥虫上鞭毛体（epimastigote）阶段的细胞表面亚蛋白质组（subproteome）进行了表征。为制备富集上鞭毛体质膜蛋白的样品，我们优化并评估了两种不同的实验方法：第一种方法基于完整活细胞的细胞表面胰蛋白酶消化，即“刮削法（Shave）”；第二种方法则先对细胞表面蛋白质进行生物素标记（biotinylation），随后通过链霉亲和素亲和层析（streptavidin affinity chromatography）分离被标记的蛋白质。两种克氏锥虫亚蛋白质组样品均通过液相色谱-串联质谱（LC-MS/MS）进行分析。结果表明，这两种方法能够为该寄生虫的质膜亚蛋白质组提供全面且互补的信息。