Richardson C, Behnke W D, Freisheim J H, Blumenthal K M
Biochim Biophys Acta. 1978 Dec 20;537(2):310-9. doi: 10.1016/0005-2795(78)90514-7.
The complete primary structure of the alpha-subunit of the lectin from the pea (Pisum sativum) has been determined using a combination of tryptic and staphylococcal protease digestion, purification using Sephadex gel filtration and high-voltage electrophoresis followed by either manual or automated Edman degradation. The molecular weight of the alpha-subunit from sequence data and gel filtration in guanidine-HCl is close to 5800, which is lower than that determined by sedimentation equilibrium techniques. The sequence reveals considerable homology to concanavalin A and near identity to the alpha-subunit of the lentil lectin (Lens culenaris). As in the case of the lentil alpha-subunit, the alpha-methyl glucose binding site(s) are not present in this region, nor are the S1 and S2 metal ion binding sites as judged by homology consideration, though the residues for the S3 lanthanide binding (Glu 87 and Asp 136) are conserved from the available data on the alpha- and beta-subunits. Preliminary metal exchange experimens on the intact pea lectin indicate some differnces in the metal exchange properties of this lectin compared to concanavalin A, and therefore possible ligand variations in this region of the beta-subunit.
通过胰蛋白酶和葡萄球菌蛋白酶消化相结合、利用葡聚糖凝胶过滤和高压电泳进行纯化，随后进行手动或自动的埃德曼降解，已确定了豌豆（Pisum sativum）凝集素α亚基的完整一级结构。根据序列数据和在盐酸胍中的凝胶过滤，α亚基的分子量接近5800，低于通过沉降平衡技术测定的分子量。该序列显示与伴刀豆球蛋白A有相当的同源性，与小扁豆凝集素（Lens culenaris）的α亚基几乎相同。与小扁豆α亚基的情况一样，该区域不存在α-甲基葡萄糖结合位点，根据同源性考虑，也不存在S1和S2金属离子结合位点，不过从α亚基和β亚基的现有数据来看，S3镧系元素结合位点的残基（Glu 87和Asp 136）是保守的。对完整豌豆凝集素进行的初步金属交换实验表明，与伴刀豆球蛋白A相比，该凝集素的金属交换特性存在一些差异，因此β亚基的该区域可能存在配体差异。
