Rhoads M L, Fetterer R H
United States Department of Agriculture, Beltsville Agricultural Research Center, Maryland 20705.
J Parasitol. 1994 Oct;80(5):756-63.
Extrinsic radioiodination experiments have shown that male and female adults of Haemonchus contortus (BPL strain) express a stage-specific set of surface-associated proteins with apparent molecular mass values of 30, 58, 81, and 143 kDa. A quantitatively different pattern of iodinated surface proteins is expressed by adults of the PPR strain of H. contortus, whereas the pattern of iodinated proteins expressed by Haemonchus similis is qualitatively distinct (38, 68, and 121 kDa). The 58-, 81-, and 143-kDa proteins of the BPL strain are glycosylated, whereas the 30-kDa protein is not. The binding of wheat germ agglutinin to the surface glycoproteins was inhibited by the trimer of N-acetylglucosamine (N,N,N-triacetylchitotroise) but not by the monosaccharide, indicating the presence of chitin-like homopolymers. The carbohydrate portion of the 58-kDa protein is N-linked and accounts for 30% of its apparent mass. Under nonreducing conditions, the 58-kDa glycoprotein forms a high molecular mass polymer that is unable to penetrate a 10% acrylamide gel. The 143- and 81-kDa surface glycoproteins were not hydrolyzed by either N- or O-glycanase, indicating unusual modifications to the saccharide-linkage and rendering it resistant to glycosidase digestion. The 30-, 58-, and 143-kDa purified surface proteins produced distinct peptide maps with Staphylococcus aureus V8 protease.
体外放射性碘化实验表明，捻转血矛线虫（BPL株）的成年雌雄虫表达一组阶段特异性的表面相关蛋白，其表观分子量分别为30、58、81和143 kDa。捻转血矛线虫PPR株的成虫表达的碘化表面蛋白模式在数量上有所不同，而相似血矛线虫表达的碘化蛋白模式在质量上则明显不同（38、68和121 kDa）。BPL株的58、81和143 kDa蛋白是糖基化的，而30 kDa蛋白不是。麦胚凝集素与表面糖蛋白的结合可被N-乙酰葡糖胺三聚体（N,N,N-三乙酰壳三糖）抑制，但不能被单糖抑制，这表明存在几丁质样均聚物。58 kDa蛋白的碳水化合物部分是N-连接的，占其表观质量的30%。在非还原条件下，58 kDa糖蛋白形成一种高分子量聚合物，无法穿透10%的丙烯酰胺凝胶。143和81 kDa的表面糖蛋白都不能被N-糖苷酶或O-糖苷酶水解，这表明其糖链连接有异常修饰，使其对糖苷酶消化具有抗性。30、58和143 kDa的纯化表面蛋白用金黄色葡萄球菌V8蛋白酶产生了不同的肽图。
