Tribbick G, Edmundson A B, Mason T J, Geysen H M
Coselco Mimotopes Pty Ltd, Commonwealth Serum Laboratories, Parkville, Victoria, Australia.
Mol Immunol. 1989 Jul;26(7):625-35. doi: 10.1016/0161-5890(89)90044-8.
The urinary light chain dimer and serum monoclonal IgG1 protein from a patient (Mcg) with multiple myeloma and amyloidosis were systematically tested for their binding activities to peptides presented on solid supports. The system was validated using a series of enkephalins, beta-casomorphins and DNP-lysine derivatives which were known to complex with the dimer. Sets of peptide ligands binding to the proteins were constructed by incremental additions of amino acid residues to minimal binding units [Geysen et al., J. Immun. Meth. 102, 259-274 (1987)]. Both the amino acid sequences and the combinations of optical isomers were optimized at each stage of the syntheses. Binding could be demonstrated for ligands ranging in size from a tethered single amino acid to pentapeptides. At the dipeptide levels, the dimer and the IgG1 protein showed different preferences (Hp versus qf, where lower case letters designate D-amino acid residues). However, in a tetrapeptide ligand (qfHp) for the dimer, both of these initial preferences had converged. With few exceptions, the IgG1 molecule showed binding activity for the ligands developed for the dimer. Two sets of selected peptides, one based on Hp and the other on mW, were synthesized for diffusion into crystals of the dimer. X-ray analyses showed that these peptides bound exclusively in the main binding cavity between the "variable" domains of the dimer. As predicted from the ELISA results with tethered ligands, the relative occupancies in the crystals followed the order of tetrapeptide greater than tripeptide much greater than dipeptide. The crystallographic studies confirmed that peptides with very different sequences can bind in the same cavity.
对一名患有多发性骨髓瘤和淀粉样变性的患者（Mcg）的尿轻链二聚体和血清单克隆IgG1蛋白与固相支持物上呈现的肽的结合活性进行了系统测试。该系统使用一系列已知与二聚体复合的脑啡肽、β-酪蛋白吗啡和DNP-赖氨酸衍生物进行了验证。通过向最小结合单元逐步添加氨基酸残基构建了与这些蛋白质结合的肽配体集[Geysen等人，《免疫学方法杂志》102，259 - 274（1987）]。在合成的每个阶段，氨基酸序列和光学异构体组合均得到优化。对于大小从连接的单个氨基酸到五肽的配体，均可证明有结合。在二肽水平，二聚体和IgG1蛋白表现出不同的偏好（Hp对qf，其中小写字母表示D-氨基酸残基）。然而，在二聚体的一种四肽配体（qfHp）中，这两种初始偏好已经趋同。几乎无一例外，IgG1分子对为二聚体开发的配体表现出结合活性。合成了两组选定的肽，一组基于Hp，另一组基于mW，用于扩散到二聚体晶体中。X射线分析表明，这些肽仅结合在二聚体“可变”结构域之间的主要结合腔中。正如用连接配体的ELISA结果所预测的，晶体中的相对占有率遵循四肽大于三肽远大于二肽的顺序。晶体学研究证实，具有非常不同序列的肽可以结合在同一腔中。
