相关实验视频

Updated: Jul 11, 2025

Studying DNA Looping by Single-Molecule FRET

Studying DNA Looping by Single-Molecule FRET

Published on: June 28, 2014

大分子拥挤有力地刺激了Mycobacterium结核病DNA旋转酶的DNA超卷活动

Zifang Deng¹, Prem Chapagain², Fenfei Leng¹

¹Biomolecular Science Institute, Florida International University, Miami, Florida, USA; Department of Chemistry & Biochemistry, Florida International University, Miami, Florida, USA.

The Journal of biological chemistry

|November 9, 2023

概括

像聚乙烯糖醇 (PEG) 和聚乙烯醇 (PVA) 这样的宏分子拥挤剂显著增强了Mycobacterium tuberculosis (Mtb) 的DNA旋转酶活性. 这些拥挤条件改善了酶动力学和DNA超,为细胞酶过程提供了洞察力.

科学领域:

生物化学生物化学
分子生物学分子生物学
生物物理学的生物物理.

背景情况:

在细胞中普遍存在的宏分子拥挤改变了酶的行为.
使用聚乙烯糖醇 (PEG) 和聚乙烯醇 (PVA) 等拥挤剂的体外研究对于理解细胞酶反应至关重要.
结核菌菌 (Mtb) 的DNA旋转酶活性受到其细胞环境的影响.

研究的目的:

为了研究大分子拥挤对Mtb DNA旋转酶DNA超活动的影响.
阐明在拥挤条件下观察到的酶活性变化背后的分子机制.

主要方法:

使用 Mtb DNA 陀螺酶与各种拥挤剂 (谷氨酸,糖氨酸贝他因,PEG,PVA) 的DNA 超卷试验.
稳定状态动力学研究以确定动力学参数 (K_M,V_max,k_cat).
分子动力学模拟以可视化PEG分子和DNA旋转酶子单元B之间的相互作用.

主要成果:

高度的谷氨酸,甲基甘氨酸,PEG和PVA大大刺激了Mtb DNA旋转酶超卷活动.
甘氨酸贝他因和PEG400降低了ATP和等离子体DNA的K_M,并增加了V_max/k_cat.
分子动力学模拟显示,PEG稳定了DNA旋转酶子单元B ATP盖的闭合构造,防止ATP解离.

结论:

大分子拥挤剂显著增强了Mtb DNA旋转酶活性.
观察到的刺激归因于水活性降低和排泄量增加,从而改善了酶动力学和稳定性.
研究结果提供了对拥挤的细胞环境中的酶功能的洞察.

关键词:

Mtb DNA 陀螺酶的使用方法这就是PEG PEG PEG.在PVA中使用PVA.不包括的体积.大分子分子拥挤.分子动力学模拟模拟水活动水活动水活动

更多相关视频

Author Spotlight: Unraveling the Dynamics of Eukaryotic DNA Replication Through Single-Molecule Visualization

Author Spotlight: Unraveling the Dynamics of Eukaryotic DNA Replication Through Single-Molecule Visualization

Published on: September 27, 2024

DNA Nanotubes as a Versatile Tool to Study Semiflexible Polymers

DNA Nanotubes as a Versatile Tool to Study Semiflexible Polymers

Published on: October 25, 2017

相关概念视频

DNA Topoisomerases

DNA Topoisomerases

Topoisomerases are enzymes that relax overwound DNA molecules during various cell processes, including DNA replication and transcription. These enzymes regulate positive and negative DNA supercoiling without changing the nucleotide sequence. DNA overwinding in a clockwise direction results in positively supercoiled DNA, whereas underwinding in a counterclockwise direction produces negatively supercoiled DNA.
Types and Mechanism of action
Topoisomerases are divided into two main types. ...

Coordination of Gene Expression Processes in Bacteria

Coordination of Gene Expression Processes in Bacteria

The DNA replication, transcription, and translation processes are intricately coupled in bacteria, allowing efficient gene expression and rapid protein synthesis. While this physical and functional coordination is advantageous, it introduces challenges that bacteria overcome through specific regulatory mechanisms.Coupling of Replication, Transcription, and TranslationThe coupling of replication, transcription, and translation is a hallmark of bacterial gene expression. As the replisome unwinds...

Stringent Response in E. coli

Stringent Response in E. coli

Bacterial growth is closely tied to nutrient availability, with cells proliferating exponentially under favorable conditions and entering a stationary phase when resources become scarce. This transition is mediated by a regulatory mechanism known as the stringent response, which allows bacteria to adapt to nutrient deprivation by modulating gene expression and metabolic activity.During nutrient scarcity, intracellular amino acid levels decline. It results in the accumulation of uncharged tRNAs...

Single-Strand DNA Binding Proteins

Single-Strand DNA Binding Proteins

For successful DNA replication, the unwinding of double-stranded DNA must be accompanied by stabilization and protection of the separated single strands of the DNA. This crucial task is performed by single-strand DNA-binding (SSB) proteins. They bind to the DNA in a sequence-independent manner, which means that the nitrogenous bases of the DNA need not be present in a specific order for binding of SSB proteins to it. The binding of SSB proteins straightens single-stranded DNA (ssDNA) and makes...