Further characterization of the combining sites of Bandeiraea (Griffonia) simplicifolia lectin-I, isolectin A(4).
Further characterization of the combining sites of Bandeiraea (Griffonia) simplicifolia lectin-I, isolectin A(4).
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Bandeiraea (Griffonia) simplicifolia 凝集素-I、异凝集素 A(4) 结合位点的进一步表征。
DOI：
10.1093/glycob/9.11.1161
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发表时间：
1999
期刊：
影响因子：
4.3
通讯作者：
Kabat,EA
中科院分区：
文献类型：
--
作者：
Wu,AM;Wu,JH;Chen,YY;Song,SC;Kabat,EA
Bandeiraea (Griffonia) simplicifolialectin-I、isolectin A4(GS I-A4) 对人类结肠癌细胞系具有细胞毒性，是源自其种子提取物的两个凝集素家族之一。它仅包含亚基 A 的同源寡聚体，并且对 GalNAcα1→ 最具特异性。为了更详细地阐明 GS I-A4-糖缀合物相互作用，通过酶联凝集素吸附剂测定 (ELLSA) 和凝集素-糖蛋白相互作用的抑制进一步表征了该凝集素的结合位点。这项研究表明，所测试的含 Tn 糖蛋白（由哺乳动物唾液糖蛋白（犰狳、无唾液仓鼠舌下糖蛋白、无唾液绵羊、牛和猪下颌下糖蛋白）组成）与 GS I-A4 牢固结合。在迄今为止测试的单价抑制剂中，p-NO2-苯基α GalNAc 是最有效的，这表明疏水力在这种凝集素的相互作用中很重要。 GS I-A4 能够在寡糖的非还原端容纳单糖 GalNAc。这表明凝集素的结合位点是浅腔。在测试作为 GS I-A4 结合抑制剂的寡糖和单糖中，效力等级为： GalNAcα1→3GalNAcβ1→3Galα1→4Galβ1→4Glc（福斯曼五糖）> GalNAcα1→3(lFucα1→2)Gal（A 型血）> GalNAc > Galα1→4Gal > Galα1→3Gal（血型） B 样）> Gal。
Bandeiraea (Griffonia) simplicifolialectin-I, isolectin A4(GS I-A4), which is cytotoxic to the human colon cancer cell lines, is one of two lectin families derived from its seed extract. It contains only a homo-oligomer of subunit A, and is most specific for GalNAcα1→. In order to elucidate the GS I-A4-glycoconjugate interactions in greater detail, the combining site of this lectin was further characterized by enzyme linked lectino-sorbent assay (ELLSA) and by inhibition of lectin-glycoprotein interactions. This study has demonstrated that the Tn-containing glycoproteins tested, consisting of mammalian salivary glycoproteins (armadillo, asialo-hamster sublingual, asialo-ovine, -bovine, and -porcine submandibular), are bound strongly by GS I-A4. Among monovalent inhibitors so far tested, p-NO2-phenylα GalNAc is the most potent, suggesting that hydrophobic forces are important in the interaction of this lectin. GS I-A4is able to accommodate the monosaccharide GalNAc at the nonreducing end of oligosaccharides. This suggests that the combining site of the lectin is a shallow cavity. Among oligosaccharides and monosaccharides tested as inhibitors of the binding of GS I-A4, the hierarchy of potencies are: GalNAcα1→3GalNAcβ1→3Galα1→4Galβ1→4Glc (Forssman pentasaccharide) > GalNAcα1→3(lFucα1→2)Gal (blood group A) > GalNAc > Galα1→4Gal > Galα1→3Gal (blood group B-like) > Gal.