对内波病毒3C类蛋白酶的AlphaFold建模为其多样化的基质特异性提供了新的见解
1Summerland Research and Development Centre, Agriculture and Agri-Food Canada, 4200 Highway 97, V0H 1Z0, Summerland, BC, Canada.
Virology
|December 5, 2023
概括
植物尼波病毒蛋白酶比典型的皮科纳病毒3C蛋白酶具有更广泛的基质特异性. 结构建模揭示了关键的S1和S4子站点特征,影响了nepovirus分离站点偏好.
科学领域:
- 结构生物学是结构生物学.
- 病毒学 病毒学
- 生物化学 生物化学
背景情况:
- 皮科纳病毒3C蛋白酶 (3Cpro) 通常在谷氨酸之后分裂.
- 植物尼波病毒3C类蛋白酶 (3CLpro) 显示更广泛的特异性,在各种残留物后分裂.
研究的目的:
- 与3Cpro相比,研究尼波病毒3CLpro不同基底特异性的结构基础.
- 为了建模十二个选定的尼波病毒3CLpro结构,代表六种基质特异性.
主要方法:
- 利用AlphaFold生成12个选定的尼波病毒3C类蛋白酶的结构模型.
- 分析了蛋白酶S1和S4子站点的结构和电荷.
主要成果:
- 在S1亚站点特征和残留物接受度之间观察到有利的相关性.
- 在P1位置附近保存的阿斯巴酸盐残留物解释了对负电荷残留物的偏差.
- 一个狭窄的S4亚位点和特定的残留物 (histidine,serine) 决定了葡萄藤风叶病毒蛋白酶在P4.4处对血清的特异性.
结论:
- 尼波病毒3CLpro子站点的结构特征决定了它们独特的基质裂解偏好.
- AlphaFold建模提供了对蛋白酶特异性决定因素的洞察,有助于理解病毒演变和功能.
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