The binding process of A9 peptide toward HER2‐DIVMP, a synthetic model of the receptor domain IV, was studied by using the surface plasmon resonance (SPR) technique, with the aim of validating it as a fast and reliable screening method for selecting peptide ligands specifically targeting a domain of their target. To investigate the structural basis of A9 binding to the model of HER2‐DIVMP, multiple ligand‐based nuclear magnetic resonance (NMR) methods were applied. The use of saturation transfer difference (STD) and WaterLOGSY NMR experiments identified key residues in the peptide for the receptor binding. Moreover, the bound conformation of the A9 peptide was obtained using transferred nuclear Overhauser effect spectroscopy (trNOESY) experiments. The NMR data revealed an extended binding surface that confirms an in silico model previously reported. These structural findings could provide good starting points for future lead structures optimization specific for the receptor target.

中文翻译：

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A9肽与HER2受体模型系统之间的分子相互作用的SPR和NMR表征：一种选择特定于其靶标的肽结构的片段方法。

利用表面等离振子共振（SPR）技术研究了A9肽与受体域IV合成模型HER2-DIVMP的结合过程，旨在将其验证为一种快速可靠的筛选肽配体的方法专门针对其目标领域。为了研究A9与HER2-DIVMP模型结合的结构基础，应用了多种基于配体的核磁共振（NMR）方法。使用饱和转移差异（STD）和WaterLOGSY NMR实验确定了肽中受体结合的关键残基。此外，使用转移核Overhauser效应光谱法（trNOESY）实验获得了A9肽的结合构象。NMR数据显示结合表面扩展，这证实了先前报道的计算机模型。这些结构上的发现可以为未来针对受体靶标的铅结构优化提供良好的起点。