和GTP结合的合驱动了Acinetobacter baumannii ZigAA中的G域折叠
Maximillian K Osterberg1, Ally K Smith2, Courtney Campbell3
1Department of Chemistry, Indiana University, Bloomington, Indiana.
Biophysical journal
|March 9, 2024
概括
Acinetobacter baumannii ZigA金属沙佩龙与和核酸结合,与GTP结合稳定了比GDP更多的蛋白质. 这种金属核酸结合会影响蛋白质的结构和功能,对细菌的生存至关重要.
科学领域:
- 生物化学 生物化学
- 结构生物学 结构生物学
- 微生物学 微生物学
背景情况:
- COG0523蛋白,或核酸依赖的金属沙佩龙,是鲜为人知的P环G3E GTPases.
- 这些蛋白质对于细菌病原体在对抗宿主营养免疫力的生存至关重要.
研究的目的:
- 阐明一个COG0523蛋白质Acinetobacter baumannii (Ab) ZigA的结构,动态和功能.
- 为了研究Zn(II) 的协调和AbZigA中的金属和核酸结合之间的热力学联系.
主要方法:
- 射线吸收光谱 (XAS) 用于确定Zn (II) 协调.
- 全球热力学测量和-交换质谱 (HDX-MS) 用于研究蛋白质动力学和稳定性.
- 金属和核酸结合的热力学分析.
主要成果:
- AbZigA使用CXCC基因中的三个半氨酸协调Zn{\displaystyle {Zn}{\displaystyle {Zn}{\displaystyle {N}}{\displaystyle {Zn}{\displaystyle {Zn}{\displaystyle {N}{\displaystyle {Zn}{\displaystyle {Zn}{\displaystyle {Zn}{\displaystyle {N}{\displaystyle {Zn}{\displaystyle {Zn}{\displaystyle {Zn}{\displaystyle {N}{\frac {N}{O}}}}}}) 组合,形成一个S3{\displaystyle S3{\frac {N}{\frac {N}{\frac {N}{\frac {N}{\frac {O}{O}{O}}}}}}) 复合体.
- Zn(II) 和关氨酸核酸结合是热力学相关的,有利于GTP而不是GDP.
- 核酸结合稳定了G域,G2循环的动态对核酸状态敏感.
- 确定了一个对核酸状态敏感的潜在客户端蛋白质结合口袋.
结论:
- AbZigA的Zn(II) 协调不同于相关蛋白质,突出显示了家族的多样性.
- 和GTP/GDP的合结合影响了AbZigA的结构和动态.
- 这些发现为AbZigA金属沙佩龙在细菌生存中的功能提供了一个模型.
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