Department of Medicine, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California, United States of America.
PLoS One. 2010 Dec 16;5(12):e14360. doi: 10.1371/journal.pone.0014360.
Griffithsin, a 121-residue protein isolated from a red algal Griffithsia sp., binds high mannose N-linked glycans of virus surface glycoproteins with extremely high affinity, a property that allows it to prevent the entry of primary isolates and laboratory strains of T- and M-tropic HIV-1. We used the sequence of a portion of griffithsin's sequence as a design template to create smaller peptides with antiviral and carbohydrate-binding properties.
METHODOLOGY/RESULTS: The new peptides derived from a trio of homologous β-sheet repeats that comprise the motifs responsible for its biological activity. Our most active antiviral peptide, grifonin-1 (GRFN-1), had an EC50 of 190.8±11.0 nM in in vitro TZM-bl assays and an EC(50) of 546.6±66.1 nM in p24gag antigen release assays. GRFN-1 showed considerable structural plasticity, assuming different conformations in solvents that differed in polarity and hydrophobicity. Higher concentrations of GRFN-1 formed oligomers, based on intermolecular β-sheet interactions. Like its parent protein, GRFN-1 bound viral glycoproteins gp41 and gp120 via the N-linked glycans on their surface.
Its substantial antiviral activity and low toxicity in vitro suggest that GRFN-1 and/or its derivatives may have therapeutic potential as topical and/or systemic agents directed against HIV-1.
从红藻 Griffithsia sp. 中分离得到的 121 个残基的蛋白 Griffithsin，与病毒表面糖蛋白上的高甘露糖 N-连接聚糖具有极高的亲和力，这种特性使其能够阻止原发性分离株和实验室株 T-和 M-嗜性 HIV-1 的进入。我们使用 Griffithsin 序列的一部分作为设计模板，创建了具有抗病毒和碳水化合物结合特性的较小肽。
方法/结果：这些新肽源自三个同源的β-折叠重复序列，这些序列构成了其生物活性的基序。我们最有效的抗病毒肽 grifonin-1（GRFN-1）在体外 TZM-bl 测定中的 EC50 为 190.8±11.0 nM，在 p24gag 抗原释放测定中的 EC(50)为 546.6±66.1 nM。GRFN-1 表现出相当大的结构可塑性，在极性和疏水性不同的溶剂中呈现不同的构象。较高浓度的 GRFN-1 基于分子间的β-折叠相互作用形成寡聚物。与母体蛋白一样，GRFN-1 通过其表面的 N-连接聚糖结合病毒糖蛋白 gp41 和 gp120。
其在体外具有显著的抗病毒活性和低毒性，表明 GRFN-1 和/或其衍生物可能具有作为针对 HIV-1 的局部和/或全身治疗剂的治疗潜力。
