Departamento de Biología, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Apartado Postal No. 187, Guanajuato, Gto. 36000, Mexico.
Exp Parasitol. 2010 Apr;124(4):459-65. doi: 10.1016/j.exppara.2009.12.014. Epub 2010 Jan 4.
Despite their well recognized importance in pathogenesis of Entamoeba histolytica there are few studies dealing with the assembly and secretion of glycoproteins that participate in the adhesion to target cells and in the dissemination of the parasite in infected tissues. Some of these studies refer to the identification and, in some cases, the characterization of glycosyl transferases and glycosidases involved in the biosynthesis of these macromolecules as well as to compartments involved in the amoeba dolichol-linked glycosylation pathway. While an N-glycan trimming alpha-mannosidase has been demonstrated in E. histolytica, little is known on its cellular distribution and properties. Here we describe the presence and partial biochemical characterization of soluble and MMF-associated forms of alpha-mannosidase and the separation of at least three internal membrane structures enriched with this glycosidase. Results are discussed in terms of the possible identity of alpha-mannosidase activity and the potential precursor-product relationship between the two enzyme forms.
尽管在溶组织内阿米巴的发病机制中，这些糖蛋白的组装和分泌具有重要作用，但目前仅有少数研究涉及到参与黏附靶细胞和寄生虫在感染组织中传播的糖蛋白。其中一些研究涉及到鉴定，在某些情况下，还涉及到参与这些大分子生物合成的糖基转移酶和糖苷酶的特征，以及涉及到阿米巴多萜醇连接糖基化途径的隔室。虽然已经在溶组织内阿米巴中证明存在 N-糖链修剪α-甘露糖苷酶，但对其细胞分布和特性知之甚少。在这里，我们描述了可溶性和 MMF 相关形式的α-甘露糖苷酶的存在和部分生化特征，以及至少三种富含这种糖苷酶的内膜结构的分离。结果将根据α-甘露糖苷酶活性的可能同一性以及两种酶形式之间的潜在前体-产物关系进行讨论。
