Ohio State Biochemistry Program, The Ohio State University, Columbus, 43210, United States.
ACS Chem Biol. 2012 Apr 20;7(4):761-9. doi: 10.1021/cb200450w. Epub 2012 Feb 13.
The human immunodeficiency virus type 1 (HIV-1) capsid protein (CA) plays a critical role in the viral life cycle. The C-terminal domain (CTD) of CA binds to human lysyl-tRNA synthetase (hLysRS), and this interaction facilitates packaging of host cell tRNA(Lys,3), which serves as the primer for reverse transcription. Here, we report the library synthesis, high-throughput screening, and identification of cyclic peptides (CPs) that bind HIV-1 CA. Scrambling or single-residue changes of the selected peptide sequences eliminated binding, suggesting a sequence-specific mode of interaction. Two peptides (CP2 and CP4) subjected to detailed analysis also inhibited hLysRS/CA interaction in vitro. Nuclear magnetic resonance spectroscopy and mutagenesis studies revealed that both CPs bind to a site proximal to helix 4 of the CA-CTD, which is the known site of hLysRS interaction. These results extend the current repertoire of CA-binding molecules to a new class of peptides targeting a novel site with potential for development into novel antiviral agents.
人类免疫缺陷病毒 1 型（HIV-1）衣壳蛋白（CA）在病毒生命周期中起着关键作用。CA 的 C 末端结构域（CTD）与人类赖氨酸 tRNA 合成酶（hLysRS）结合，这种相互作用促进了宿主细胞 tRNA（Lys，3）的包装，该 tRNA 作为逆转录的引物。在这里，我们报告了库合成、高通量筛选和鉴定与 HIV-1 CA 结合的环肽（CPs）。所选肽序列的乱序或单个残基变化消除了结合，表明存在序列特异性相互作用模式。经过详细分析的两种肽（CP2 和 CP4）也在体外抑制了 hLysRS/CA 相互作用。核磁共振波谱和突变研究表明，这两种 CP 都结合到 CA-CTD 中螺旋 4 附近的一个位点，这是已知的 hLysRS 相互作用位点。这些结果将 CA 结合分子的现有库扩展到针对具有开发成新型抗病毒药物潜力的新位点的新型肽。
