霍乱病毒病毒的结构性决定因素FeoB核酸乱交性
Mark Lee1, Kate Magante1, Camilo Gómez-Garzón2
1Department of Chemistry and Biochemistry, University of Maryland, Baltimore County, Baltimore, Maryland, USA.
The Journal of biological chemistry
|August 11, 2024
概括
霍乱病毒中的FeoB蛋白质运输铁,其调节域 (NFeoB) 显示核酸乱交. 结构研究揭示了NFeoB如何适应不同的核酸,帮助病原体吸收铁.
科学领域:
- 微生物学 微生物学
- 结构生物学 结构生物学
- 生物化学 生物化学
背景情况:
- 铁 (Fe2+) 对病原性细菌至关重要,包括霍乱病毒 (霍乱病原体).
- Feo系统,特别是FeoB,对于V. cholerae的细胞内铁运输至关重要.
- 调节性NFeoB域的核酸特异性 (GTP特异性与NTP杂交性) 在结构上以前没有被描述.
研究的目的:
- 阐明FeoB核酸杂交的结构和机制基础.
- 了解NFeoB如何区分关氨酸和腺氨酸核酸.
- 为FeoB在病原体铁获取中的作用提供结构框架.
主要方法:
- VcNFeoB的X射线晶体学 (apo和GDP绑定的形式).
- 结构生物信息学分析以确定关键残留物.
- 位点定向突变发生 (N150T) 和X射线晶体学.
- 核酸结合热力学的异热定位热量计 (ITC).
- 用AlphaFold建模来预测形状变化.
主要成果:
- VcNFeoB与GTP特定的NFeoB共享了正规的G蛋白折叠,尽管它是无序的.
- 突变残留150 (N150T) 显示在关氨基基周围发生了改变的键.
- ITC 显示了与关氨酸核酸的类似结合,但与 WT 和 N150T 的腺氨酸核酸有不同的行为.
- 阿尔法折叠模型显示了对ADP和ATP的反应中的形状变化,这有助于特异性.
结论:
- 提供了对FeoB核酸乱交的结构性见解.
- 特定的残留物和形状变化决定了NFeoB.中的核酸特异性.
- FeoB的杂乱性可能是病原体在不同的代谢条件下维持铁水平的适应策略.
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