人类诺罗病毒ProPol前体聚合酶域的活性和冷EM结构
Alice M McSweeney1, Alice-Roza Eruera1,2, Geena M McKenzie-Goldsmith1
1Department of Microbiology and Immunology, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand.
Journal of virology
|October 30, 2024
概括
与成熟的聚合酶相比,人类诺病毒蛋白酶聚合酶 (ProPol) 显示出明显的酶活性和抗病毒反应. 这项研究揭示了ProPol前体的独特特性,有助于理解诺罗病毒复制.
科学领域:
- 病毒学 病毒学
- 分子生物学分子生物学
- 结构生物学 结构生物学
背景情况:
- 人类诺罗病毒 (HuNV) 引起广泛的胃肠炎,复制机制尚不清楚.
- 病毒聚蛋白加工产生前体蛋白,包括蛋白酶聚合酶 (ProPol),对于复制至关重要.
- 前体ProPol和成熟聚合酶之间的活性和结构差异在很大程度上是未知的.
研究的目的:
- 调查HuNV ProPol.的新型聚合酶活性,蛋白质结构和抗病毒抑制特征.
- 将ProPol的酶性质和抗病毒反应与成熟的诺病毒聚合酶 (Pol) 进行比较.
- 阐明ProPol聚合酶域的结构特征.
主要方法:
- 使用各种RNA模板和核糖核酸,评估了GII ProPol的新酶效率 (kcat/Km).
- 使用冷电子显微镜 (2.6 Å分辨率) 确定了HuNV ProPol的聚合酶域的结构.
- 评估了加利迪西维三酸盐和PPNDS对GII ProPol聚合酶活性的抑制作用.
主要成果:
- 在大多数模板上,GII ProPol的酶效率与成熟的GII Pol相等或更高,并且在多种模板上具有独特的活性.
- 冷EM揭示了与成熟的Pol相似的ProPol聚合酶域结构,其中保留了活性位点结构.
- 加利迪西维尔三酸盐和PPNDS抑制了GII的ProPol活性,与成熟的Pol相比,ProPol显示了不同的IC50值.
结论:
- 与成熟的Pol.相比,HuNV ProPol具有重叠和独特的酶特性.
- 的结构类似于成熟的,这表明基质相互作用决定了其独特的活性.
- 普罗波尔对抗病毒药物的反应不同,突出了其独特的生化特征和作为治疗点的潜力.
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