在初级蛋白质生物发生过程中的陪伴者依赖与in vitro重新折叠过程中的陪伴者依赖不相关
Divya Yadav1, İdil I Demiralp1, Mark Fakler1
1Department of Chemistry, Johns Hopkins University, Baltimore, MD 21218, USA.
bioRxiv : the preprint server for biology
|July 4, 2025
概括
许多蛋白质需要分子伴侣来正确折叠. 这项研究表明,在体外无法重新折叠的蛋白质在体内不一定依赖伴侣,这表明对许多大肠杆菌蛋白质的共同翻译折叠是关键.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 结构生物学 结构生物学
背景情况:
- 蛋白质需要分子陪伴者才能正确地折叠成功能形式.
- 实验室研究表明,许多蛋白质在没有伴侣的情况下很难重新折叠,但体内作用可能有所不同.
- 有限蛋白解质质谱法 (LiP-MS) 是一种检测蛋白质结构的技术.
研究的目的:
- 研究E. coli中删除关键分子伴侣,触发因子和DnaKJ的体内结构影响.
- 为了确定蛋白质在体外重新折叠能力较差的蛋白质是否更依赖于在体内折叠的陪伴者.
- 探索共同翻译折叠在蛋白质生物生成中的作用.
主要方法:
- 利用有限蛋白质解质质谱法 (LiP-MS) 来评估伴侣删除后的蛋白质组结构变化.
- 进行生物化学和生物物理分析,以验证对特定蛋白质的发现,如糖酸酶 (PGK).
主要成果:
- 删除DnaKJ显著扰乱了许多可溶性大肠杆菌蛋白质的结构.
- 触发因子的删除对蛋白质结构的影响最小.
- 在体外重新折叠不良的蛋白质在体内不一定依赖伴侣.
- 糖分酶PGK,尽管体外重新折叠很差,但在伴侣删除后保持了它的结构,表明有效的协同翻译折叠.
结论:
- 同翻译折叠对于许多大肠杆菌蛋白质的原生结构获取至关重要,特别是那些被识别为伴侣非回折者.
- 同翻译折叠的矢量过程可以充当主要的"护卫"机制,减少对其他护卫系统的依赖.
- 在体内蛋白质折叠途径,特别是在合成过程中,是关键的,并且可能绕过对某些蛋白质的翻译后护卫辅助的需要.
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