合规子状态调节二酸盐减少酶中的化物转移
Ian F Thorpe1, Charles L Brooks
1Department of Molecular Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA.
Journal of the American Chemical Society
|September 15, 2005
概括
双叶酸减少酶 (DHFR) 突变通过改变蛋白质动态影响化物转移障碍. 模拟显示,不同的酶子状态与各种反应障碍相关,解释了长距离的突变效应.
科学领域:
- 生物化学 生物化学
- 酶学 是一种酶学.
- 计算生物学 计算生物学
背景情况:
- 叶酸减少酶 (DHFR) 对于叶酸代谢至关重要.
- 之前的研究发现了与化物转移反应障碍相关的蛋白质特征.
- 了解酶动态是阐明催化机制的关键.
研究的目的:
- 用模拟来确定野生型DHFR和G121V/G121S突变体中的化物转移屏障.
- 为了研究完整的反应路径和反应事件.
- 为了将蛋白质动态和波动与化物转移屏障高度相关联.
主要方法:
- 进行了潜在的平均力 (PMF) 模拟.
- 分析自由能源障碍和结构组合的分析.
- 研究蛋白质波动和振动模式.
主要成果:
- PMF计算证实了先前关于反应障碍的研究趋势.
- 与化物转移屏障高度相关的模拟波动.
- 促进化物转移的振动模式在降低屏障的模拟中显示出更大的振幅.
结论:
- 在潜在能量格局上的离散酶子状态产生了不同的化物转移障碍.
- 在DHFR121位的突变通过预先组织的蛋白质环境和亚基分布产生远程影响.
- 酶动力学与催化效率和突变效应密切相关.
相关概念视频
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When the pH of arterial blood rises above 7.45, it results in a condition called alkalosis. Conversely, a drop below 7.35 leads to...
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In the kidneys, cells within the proximal convoluted tubules (PCT) and the collecting ducts secrete hydrogen ions (H+) into the tubular fluid. Specifically, in the PCT, Na+/H+ antiporters secrete H+ while reabsorbing Na+.
However, the intercalated cells in...
In the kidneys, cells within the proximal convoluted tubules (PCT) and the collecting ducts secrete hydrogen ions (H+) into the tubular fluid. Specifically, in the PCT, Na+/H+ antiporters secrete H+ while reabsorbing Na+.
However, the intercalated cells in...
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The human body employs intricate mechanisms to counteract changes in blood pH, preventing conditions like acidosis (pH < 7.35) and alkalosis (pH > 7.45). These compensatory responses aim to restore normal arterial blood pH by engaging respiratory or renal systems, depending on the source of the imbalance.
Respiratory Compensation
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