PURIFICATION AND PROPERTIES OF A D-GALACTOSE-N-ACETYL-D-GALACTOSAMINE-SPECIFIC LECTIN FROM ERYTHRINA-CRISTAGALLI
PURIFICATION AND PROPERTIES OF A D-GALACTOSE-N-ACETYL-D-GALACTOSAMINE-SPECIFIC LECTIN FROM ERYTHRINA-CRISTAGALLI
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DOI：
10.1111/j.1432-1033.1982.tb19760.x
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发表时间：
1982-01-01
期刊：
影响因子：
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通讯作者：
SHARON, N
中科院分区：
文献类型：
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作者：
IGLESIAS, JL;LIS, H;SHARON, N
从E.通过D-半乳糖衍生的Sepharose柱上的亲和层析，以高产率（75%）和均一形式分离cristagalli。它是一种糖蛋白，分子量为56，800 ±。900由2个亚基（表观分子量分别为28，000和26，000）组成，这两个亚基都是糖基化的。总碳水化合物含量为4.5%，由甘露糖、N-乙酰葡糖胺、岩藻糖和木糖组成，其量分别对应于7、4、2和2 mol/56，800 Da [道尔顿]。凝集素的氨基酸组成的特征在于高含量的酸性和羟基氨基酸、低含量的甲硫氨酸和不存在半胱氨酸。缬氨酸是唯一检测到的N-末端氨基酸。凝集素是一种金属蛋白，因为它含有0.093%的Mn和0.13%的Ca（分别为1 mol和1.9 mol/56，800 Da），这两种物质都与蛋白质紧密结合。E. Cristagalli凝集素以5-10 μ g/ml的浓度凝集所有血型的未处理的人红细胞以及兔红细胞。它在最佳浓度为约x时对人外周血T淋巴细胞有促有丝分裂作用。100 μ g/ml，但对小鼠胸腺细胞或脾细胞没有促有丝分裂作用。D-半乳糖和各种D-半乳糖苷抑制凝集素的血凝活性。N-乙酰乳糖胺是最有效的，在0.4 mM浓度下完全抑制凝集素的4个凝集单位。乳糖、N-乙酰基-D-半乳糖胺和D-半乳糖的活性分别低5、16和35倍。乳糖特异性干扰凝集素芳香区的紫外光谱。二糖与凝集素结合后获得的差谱在291 nm和282-284 nm处显示最大值，表明糖结合后蛋白质色氨酸残基的环境发生变化。
The lectin from the seeds of E. cristagalli was isolated in high yield (75%) and homogeneous form by affinity chromatography on a column of D-galactose-derivatized Sepharose. It is a glycoprotein with a MW of 56,800 .+-. 900 composed of 2 subunits (apparent MW of 28,000 and 26,000, respectively) both of which are glycosylated. The total carbohydrate content is 4.5% and it is comprised of mannose, N-acetylglucosamine, fucose and xylose in amounts corresponding to 7, 4, 2 and 2 mol/56,800 Da [daltons] respectively. The amino acid composition of the lectin is characterised by a high content of acidic and hydroxy amino acids, low content of methionine and absence of cysteine. Valine is the only N-terminal amino acid detected. The lectin is a metalloprotein in that it contains 0.093% Mn and 0.13% Ca (1 mol and 1.9 mol/56,800 Da respectively), both of which tightly bound to the protein. E. cristagalli lectin agglutinates untreated human erythrocytes of all blood types, as well as rabbit erythrocytes, at a concentration of 5-10 .mu.g/ml. It is mitogenic for human peripheral blood T lymphocytes at an optimal concentration of .apprx. 100 .mu.g/ml, but is not mitogenic for mouse thymocytes or splenocytes. D-Galactose and various D-galactosides inhibit the hemagglutinating activity of the lectin. N-Acetyllactosamine is most potent, completely inhibiting 4 agglutinating units of the lectin at 0.4 mM concentration. Lactose, N-acetyl-D-galactosamine and D-galactose are 5, 16 and 35 times less active, respectively. Lactose specifically perturbs the UV spectrum of the lectin in the aromatic region. The difference spectrum obtained upon binding of the disaccharide to the lectin shows maxima at 291 nm and 282-284 nm, indicating a change in the environment of tryptophan residues of the protein upon binding of sugar.