Tanimura F, Morioka H, Murakami Y
Department of Otolaryngology, Municipal Yamashiro Hospital, Kyoto, Japan.
Eur Arch Otorhinolaryngol. 1993;250(7):412-7. doi: 10.1007/BF00180388.
Glucosamine-binding sites were detected in Lowicryl K4M-embedded guinea pig middle ear mucosa by electron microscopy, using glucosaminyl bovine serum albumin. Incubation of ultrathin tissue sections with gold-labeled glucosaminyl bovine serum albumin (GlcN/BSA/gold) resulted in binding mainly on cilia, microvilli, rough endoplasmic reticulum and nuclei. The sugar binding was not inhibited after ultrathin sections had been digested with trypsin or neuraminidase. Various carbohydrates and glycoconjugates were tested as competitive inhibitors of GlcN/BSA/gold labeling on the tissue sections. The sugar specificity range detected by the glucosamine-binding sites included glucosamine, N-acetylglucosamine, mannose and fucose, whereas N-acetylgalactosamine, galactose and glucose were not detectable. A series of endotoxic substances such as Salmonella minnesota Re595 lipid A complex with BSA and lipopolysaccharides (LPS) derived from Escherichia coli 055:B5 or S. minnesota Re595 also competed with GlcN/BSA/gold binding. This indicates that the lipid A backbone glucosamine or other carbohydrate portions of LPS is a part of the structure recognized by glucosamine-binding sites.
利用氨基葡萄糖基牛血清白蛋白，通过电子显微镜在Lowicryl K4M包埋的豚鼠中耳黏膜中检测到了氨基葡萄糖结合位点。用金标记的氨基葡萄糖基牛血清白蛋白（GlcN/BSA/金）孵育超薄组织切片后，结合主要发生在纤毛、微绒毛、粗面内质网和细胞核上。在用胰蛋白酶或神经氨酸酶消化超薄切片后，糖结合并未受到抑制。测试了各种碳水化合物和糖缀合物作为组织切片上GlcN/BSA/金标记的竞争性抑制剂。氨基葡萄糖结合位点检测到的糖特异性范围包括氨基葡萄糖、N-乙酰氨基葡萄糖、甘露糖和岩藻糖，而N-乙酰半乳糖胺、半乳糖和葡萄糖未被检测到。一系列内毒素物质，如与牛血清白蛋白结合的明尼苏达沙门氏菌Re595脂多糖复合物以及源自大肠杆菌055:B5或明尼苏达沙门氏菌Re595的脂多糖（LPS），也与GlcN/BSA/金结合竞争。这表明脂多糖的脂质A主链氨基葡萄糖或其他碳水化合物部分是氨基葡萄糖结合位点识别结构的一部分。
