一个基变形酶-核糖体复合体揭示了新生的链处理机制
Rouven Bingel-Erlenmeyer1, Rebecca Kohler, Günter Kramer
1Institute of Molecular Biology and Biophysics, ETH Zurich, 8093 Zurich, Switzerland.
Nature
|February 22, 2008
概括
变形酶 (PDF) 通过其C端延伸直接与细菌核糖体相互作用,使新生蛋白质的高效协同翻译处理成为可能. 这种相互作用增强了细胞活力,并为蛋白质合成提供了结构性见解.
科学领域:
- 分子生物学分子生物学
- 结构生物学 结构生物学
- 细菌学 细菌学是一门学科.
背景情况:
- 在欧细菌中,信使RNA (mRNA) 导向的蛋白质合成始于formylmethionine (fMet) tRNA.
- 新生多上N端形式化甲因被变形酶 (PDF) 和甲氨基酶处理.
- 像大肠杆菌 (Escherichia coli) 这样的甲基阴性细菌中的C类-1类PDF具有C端α螺旋延伸,但它们的协同翻译机制尚不清楚.
研究的目的:
- 通过细菌变形酶 (PDF) 共同翻译蛋白质加工的机制的研究.
- 阐明大肠杆菌PDF与核糖体之间的相互作用的结构基础.
- 了解PDF与核糖体的相互作用如何影响细胞活力和蛋白质合成.
主要方法:
- 生物化学分析以证明大肠杆菌PDF和核糖体之间的直接相互作用.
- 在3.7 Å分辨率下对PDF C终端螺旋和核糖体之间的复合体进行晶体分析.
- 在PDF和核糖体之间相互作用时评估细胞活力.
主要成果:
- 生物化学证据证实大肠杆菌PDF通过其C端延伸与核糖体的直接相互作用.
- 晶体结构显示PDF的活性部位面向于核糖体道出口,用于协同翻译处理.
- PDF与核糖体之间的相互作用显著提高了细菌细胞的活力.
结论:
- PDF的C端延伸对于核糖体结合和协同翻译功能至关重要.
- 结构数据解释了蛋白质合成和新生的链处理的高效合.
- PDF-核糖体相互作用在细菌细胞生理学中起着至关重要的作用,可能涉及核糖体相关的因素,如触发因子.
相关概念视频
Termination of Translation
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Within a biological system, the DNA encodes the RNA, and the nucleotide sequence in the RNA further defines the amino acid sequence in the protein. This is referred to as “The Central Dogma of Molecular Biology” - a term coined by Francis Crick. Central dogma is a firm principle in biology that defines the flow of genetic information within any life form. The two fundamental steps in central dogma are - transcription and translation.
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Transcription is the synthesis of RNA molecules by RNA...
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Sec61 channel partners for cotranslational translocation
During cotranslational translocation, the Sec61 channel partners with the signal recognition particle (SRP), the signal recognition particle receptor (SR), and the ribosomes to transport the nascent polypeptide chain...
Post-translational Translocation of Proteins to the RER
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Targeting proteins to the ER
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Targeting proteins to the ER
Hsp40 and Hsp70 chaperone molecules bind the translated proteins in the cytosol to prevent their folding. The chaperone binding helps to keep the signal...
Proteins: From Genes to Degradation
Within a biological system, the DNA encodes the RNA, and the nucleotide sequence in the RNA further defines the amino acid sequence in the protein. This is referred to as “The Central Dogma of Molecular Biology” - a term coined by Francis Crick. Central dogma is a firm principle in biology that defines the flow of genetic information within any life form. The two fundamental steps in central dogma are - transcription and translation.
Transcription is the synthesis of RNA molecules by RNA...
Transcription is the synthesis of RNA molecules by RNA...


