Glushko A N, Apal'ko S V, Bakulina A Iu, Matveeva V A, Khrapov E A, Kostianko M V, Sil'nikov V N, Filipenko M L
Mol Biol (Mosk). 2010 Jul-Aug;44(4):699-707.
To define of possible mechanism of monoclonal antibody B2 interaction with haptens and peptide-mimotope of benzo[a]pyrene Fab-fragment structure was modeled. Antibody active centre structure was defined using docking with a number of different polyclic aromatic hydrocarbons. It was shown that active center of monoclonal antibody B2 composed of two binding pockets. Correlation was revealed between experimental and calculated data on relative free energies of monoclonal antibody B2 binding with different ligands. We found that synthetic peptide-mimotope of benzo[a]pyrene weakly competeswith benzo[a]pyrene conjugate in monoclonal antibody B2 binding. Immunization of mice with peptide-mimotope conjugate did not revealed antibodies to benzo[a]pyrene. To define structural features of peptide-mimotope of benzo[a]pyrene preliminary model of peptide-mimotope in the frame of pIII protein was calculated. It was shown that tryptophan located inside of peptide can be exhibited on a surface and accessible to antibody. Obtained modeling results could be applied for following optimizations ofbenzo[a]pyrene peptide-mimotope and active center of monoclonal antibody B2.
为了确定单克隆抗体B2与半抗原以及苯并[a]芘肽模拟表位相互作用的可能机制,对Fab片段结构进行了建模。通过与多种不同的多环芳烃对接来确定抗体活性中心结构。结果表明,单克隆抗体B2的活性中心由两个结合口袋组成。揭示了单克隆抗体B2与不同配体结合的相对自由能的实验数据和计算数据之间的相关性。我们发现,苯并[a]芘的合成肽模拟表位在单克隆抗体B2结合中与苯并[a]芘缀合物的竞争较弱。用肽模拟表位缀合物免疫小鼠未发现针对苯并[a]芘的抗体。为了确定苯并[a]芘肽模拟表位的结构特征,计算了pIII蛋白框架内肽模拟表位的初步模型。结果表明,位于肽内部的色氨酸可以暴露在表面并为抗体所接触。获得的建模结果可用于苯并[a]芘肽模拟表位和单克隆抗体B2活性中心的后续优化。