Zwitterionic dendrimer is an effective carrier, which can restore the natural conformation of peptide segments for high bioaffinity by a hydrogen bond-induced conformational constraint approach. However, it is still unknown whether the approach is applicable for the dendrimers with different geometric sizes. Therefore, the characteristics of conjugates made from zwitterionic poly(amidoamine) (PAM) and the arginine-glycine-aspartic acid (RGD) peptide were examined to elucidate the effects of the geometric sizes of the PAM dendrimer on the conformational structure and stability of the peptide. The results show that the RGD fragments had almost the same structure and stability when conjugated with PAM(G3, G4, or G5) dendrimers. However, when conjugated with PAM(G1 or G2) dendrimers, the structural stability of these fragments was found to be much worse. Also, the structure and stability of RGD segments conjugated with PAM(G3, G4, or G5) were not affected when additional EK segments were inserted. Moreover, we observed that RGD fragments conjugated with PAM(G3, G4, or G5) dendrimers were structurally stable and similar when the concentration of NaCl was 0.15 and 0.5M. Furthermore, we show that PAM(G3, G4, or G5)-RGD conjugates bind strongly to integrin αvβ3.

中文翻译：

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用于整合素 αvβ3 结合的两性离子肽-树枝状聚合物偶联物的分子模拟研究。

两性离子树枝状聚合物是一种有效的载体，可以通过氢键诱导的构象约束方法恢复肽段的天然构象以实现高生物亲和力。然而，该方法是否适用于具有不同几何尺寸的树枝状聚合物仍然未知。因此，研究了由两性离子聚酰胺胺 (PAM) 和精氨酸-甘氨酸-天冬氨酸 (RGD) 肽制成的缀合物的特性，以阐明 PAM 树枝状聚合物的几何尺寸对构象结构和稳定性的影响。肽。结果表明，当与 PAM（G3、G4 或 G5）树枝状聚合物偶联时，RGD 片段具有几乎相同的结构和稳定性。然而，当与 PAM（G1 或 G2）树枝状聚合物结合时，发现这些片段的结构稳定性要差得多。此外，当插入额外的 EK 片段时，与 PAM（G3、G4 或 G5）结合的 RGD 片段的结构和稳定性不受影响。此外，我们观察到当 NaCl 浓度为 0.15 和 0.5M 时，与 PAM（G3、G4 或 G5）树枝状聚合物缀合的 RGD 片段结构稳定且相似。此外，我们表明 PAM（G3、G4 或 G5）-RGD 偶联物与整合素 αvβ3 强烈结合。