Weis W I, Drickamer K, Hendrickson W A
Department of Biochemistry and Molecular Biophysics, Columbia University, New York, New York 10032.
Nature. 1992 Nov 12;360(6400):127-34. doi: 10.1038/360127a0.
C-type (Ca(2+)-dependent) animal lectins such as mannose-binding proteins mediate many cell-surface carbohydrate-recognition events. The crystal structure at 1.7 A resolution of the carbohydrate-recognition domain of rat mannose-binding protein complexed with an oligomannose asparaginyl-oligosaccharide reveals that Ca2+ forms coordination bonds with the carbohydrate ligand. Carbohydrate specificity is determined by a network of coordination and hydrogen bonds that stabilizes the ternary complex of protein, Ca2+ and sugar. Two branches of the oligosaccharide crosslink neighbouring carbohydrate-recognition domains in the crystal, enabling multivalent binding to a single oligosaccharide chain to be visualized directly.
C 型（依赖 Ca(2+)的）动物凝集素，如甘露糖结合蛋白，介导许多细胞表面碳水化合物识别事件。大鼠甘露糖结合蛋白的碳水化合物识别结构域与低聚甘露糖天冬酰胺寡糖复合后的 1.7 埃分辨率晶体结构表明，Ca2+与碳水化合物配体形成配位键。碳水化合物特异性由配位和氢键网络决定，该网络稳定了蛋白质、Ca2+和糖的三元复合物。寡糖的两个分支在晶体中交联相邻的碳水化合物识别结构域，使得能够直接观察到与单个寡糖链的多价结合。
