Hamazaki H
J Biol Chem. 1986 Apr 25;261(12):5455-9.
A novel lectin has been found in human plasma. The lectin was purified by affinity chromatography using an adsorbent in which 2-O-alpha-D-glucopyranosyl-O-beta-D-galactopyranosylhydroxylysine (Glc-Gal-Hyl) was coupled to Sepharose. The molecular weight of the lectin was determined by gradient gel electrophoresis to be approximately 240,000. On polyacrylamide gel electrophoresis in sodium dodecyl sulphate, the subunit had the molecular weight of 29,500. Composition analysis has shown the lectin is a glycoprotein in which 12% of the molecule consists of carbohydrate. Native human, horse, calf, sheep, rabbit, and rat erythrocytes were agglutinated by the lectin in the presence of calcium. Glc-Gal-Hyl, N-acetylated Glc-Gal-Hyl, and stachyose inhibited the hemagglutination, whereas monosaccharides, maltose, cellobiose, lactose, raffinose, galactosylhydroxylysine, and N-acetylated galactosylhydroxylysine were not inhibitory. The lectin is strongly inhibited by the desialylated bovine erythrocyte glycoprotein, which contains galactose beta 1-3galactose beta-sequence at the nonreducing termini of the sugar chains, whereas disialylated orosomucoid did not inhibit the lectin. These results indicate that the lectin recognizes the penultimate galactose residue in a hapten molecule in contrast to usual galactose-binding proteins or galactose-specific lectins, which recognize exposed, terminal galactose residues of sugar chains.
在人血浆中发现了一种新型凝集素。该凝集素通过亲和层析法进行纯化，使用的吸附剂是将2-O-α-D-吡喃葡萄糖基-O-β-D-吡喃半乳糖基羟赖氨酸（Glc-Gal-Hyl）偶联到琼脂糖上制成的。通过梯度凝胶电泳测定该凝集素的分子量约为240,000。在十二烷基硫酸钠聚丙烯酰胺凝胶电泳中，其亚基的分子量为29,500。组成分析表明该凝集素是一种糖蛋白，其中12%的分子由碳水化合物组成。在有钙存在的情况下，该凝集素能凝集天然的人、马、小牛、绵羊、兔子和大鼠的红细胞。Glc-Gal-Hyl、N-乙酰化的Glc-Gal-Hyl和水苏糖可抑制血凝，而单糖、麦芽糖、纤维二糖、乳糖、棉子糖、半乳糖基羟赖氨酸和N-乙酰化半乳糖基羟赖氨酸则无抑制作用。该凝集素受到去唾液酸化牛红细胞糖蛋白的强烈抑制，该糖蛋白在糖链的非还原末端含有半乳糖β1-3半乳糖β序列，而双唾液酸化的血清类粘蛋白则不抑制该凝集素。这些结果表明，与通常识别糖链暴露的末端半乳糖残基的半乳糖结合蛋白或半乳糖特异性凝集素不同，该凝集素识别半抗原分子中的倒数第二个半乳糖残基。
