带有药物阻碍的退出道的核糖体选择性蛋白质合成
Krishna Kannan1, Nora Vázquez-Laslop, Alexander S Mankin
1Center for Pharmaceutical Biotechnology, University of Illinois at Chicago, 900 S. Ashland Avenue, Chicago, IL 60607, USA.
Cell
|October 30, 2012
概括
针对核糖体出口道的宏类抗生素并不阻断所有蛋白质合成. 相反,它们允许基于它们的结构合成特定的蛋白质,重塑细胞蛋白质组.
科学领域:
- 分子生物学分子生物学
- 结构生物学 结构生物学
- 生物化学 生物化学
背景情况:
- 核糖体的多退出道对于新生的蛋白质折叠至关重要,并且是宏类抗生素的目标.
- 麦克罗利德被认为通过阻塞这个道来抑制蛋白质合成.
- 麦克罗利德对细胞蛋白质生产的确切影响仍然不完全理解.
研究的目的:
- 研究类抗生素对核糖体功能和蛋白质合成的影响.
- 为了确定与药物结合的核糖体是否可以合成特定的多.
- 阐明蛋白质结构在导航受阻的多化物退出道中的作用.
主要方法:
- 使用结构生物学技术来分析与药物结合的核糖体.
- 采用生物化学测试来监测在化物存在的情况下的蛋白质合成.
- 分析受影响的核糖体合成的多的结构特征.
主要成果:
- 药物结合的核糖体可以合成独特的细胞多的子集.
- 聚的穿过阻塞道的能力取决于它的结构.
- 虽然一些蛋白质绕过初始停止,但它们的合成可以在延长后停止;其他人完成翻译.
- 宏类抗生素可以选择性地改变细胞蛋白质组,而不是在全球范围内阻断蛋白质合成.
结论:
- 核糖体出口道表现出歧视性特性,受到小分子效应物的影响,如宏化物.
- 宏类抗生素不会导致蛋白质合成完全停止,而是重塑蛋白质组.
- 了解这些机制对于开发有针对性的抗生素疗法至关重要.
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