Rigothier M C, García-Rivera G, Guaderrama M, Orozco E
Parasitology Laboratory, Faculty of Pharmacy, University of Paris, Chatenay-Malabry, France.
Arch Med Res. 1992;23(2):239-41.
The 112 kDa adhesin of E. histolytica is directly involved in the cytopathogenic activity of the parasite. We describe here the purification of the 112 kDa protein by electroelution and immunoaffinity chromatography using a monoclonal antibody against the adhesin. Two proteins of 70 and 50 kDa were eluted from the immunoaffinity column along with the 112 kDa adhesin. The three proteins were recognized by monospecific polyclonal antibodies against the adhesin. The same peptides (72 and 56 kDa) were also observed after incubation of the purified intact adhesin in diethylamine buffer. Proteins of 112 and 72 kDa were found to have protease activity, evidenced by their ability to degrade gelatin. Our results indicate that the 112 kDa adhesin was specifically broken down into two polypeptides of 50-56 and 70-72 kDa. The significance of this in vivo is as yet unclear. The adhesin has proteolytic activity, which is retained in the 70-72 kDa polypeptide but not in the 50-56 kDa one.
溶组织内阿米巴的112 kDa黏附素直接参与该寄生虫的细胞致病活性。我们在此描述了通过电洗脱和免疫亲和层析法，使用针对该黏附素的单克隆抗体来纯化112 kDa蛋白。两种分子量分别为70 kDa和50 kDa的蛋白与112 kDa黏附素一同从免疫亲和柱上洗脱下来。这三种蛋白可被针对该黏附素的单特异性多克隆抗体识别。在将纯化的完整黏附素在二乙胺缓冲液中孵育后，也观察到了相同的肽段（72 kDa和56 kDa）。发现112 kDa和72 kDa的蛋白具有蛋白酶活性，这可通过它们降解明胶的能力得以证明。我们的结果表明，112 kDa黏附素被特异性地分解为两条分子量分别为50 - 56 kDa和70 - 72 kDa的多肽。其在体内的意义尚不清楚。该黏附素具有蛋白水解活性，这种活性保留在70 - 72 kDa的多肽中，而在50 - 56 kDa的多肽中则没有。
