水合水-蛋白波动的水合动态和时间尺度
Tanping Li1, Ali A Hassanali, Ya-Ting Kao
1Biophysics Program, The Ohio State University, Columbus, Ohio 43210, USA.
Journal of the American Chemical Society
|February 27, 2007
概括
球蛋白的光激发揭示了双相放松动态. 合的水蛋白运动对于缓慢的动力学至关重要,尽管模拟显示惯性放松的差异.
科学领域:
- 生物物理学的生物物理.
- 计算化学计算化学
- 蛋白质动力学 蛋白质动力学
背景情况:
- 对光激发的阿波米oglobin 的反应是理解蛋白质动态的关键.
- 水和蛋白质的相互作用显著影响生物分子功能.
研究的目的:
- 为了研究光刺激后的阿波米oglobin中的水和蛋白质动态.
- 阐明驱动放松过程的分子机制.
- 将实验结果与理论模拟进行比较.
主要方法:
- 现场定向突变发生和秒光谱学用于实验观测.
- 线性反应和不平衡分子动力学 (MD) 模拟.
- 用冷蛋白或水成分进行受约束的MD模拟.
主要成果:
- 观察了5和87 psi的时间尺度上的双相放松动态.
- 模拟MD重现了双相行为,突出了蛋白质灵活性的必要性.
- 确定合的水-蛋白运动对于缓慢动态至关重要,发生在几十个皮秒.
结论:
- 为了在模拟中观察缓慢的水动态,需要蛋白质的灵活性.
- 合的水蛋白运动对于阿波米oglobin的放松过程至关重要.
- 在模拟的惯性放松和实验中没有放松之间存在差异,这表明有理论改进的领域.
相关概念视频
01:24Protein Diffusion in the Membrane
Proteins show rotational as well as lateral diffusion across the membrane. The lateral diffusion of proteins was confirmed through the cell fusion experiment where mouse and human cells were fused, resulting in hybrid cells. When the human and mouse cells fused, the specific membrane proteins on human and mouse cells were marked with the red and green-fluorescent markers, respectively. Initially, the red and green fluorescence was located on the respective hemisphere of the cell. As time...
01:19Protein Dynamics in Living Cells
Different fluorescence-based techniques are used to study the protein dynamics in living cells. These techniques include FRAP, FRET, and PET.
Fluorescent recovery after photobleaching (FRAP) is a fluorescent-protein-based detection technique used to quantify protein movement rates within the cell. This method exposes a small portion of the cell to an intense laser beam. The laser beam causes permanent photobleaching of the fluorophore-tagged proteins in the exposed region. As the bleached...
Fluorescent recovery after photobleaching (FRAP) is a fluorescent-protein-based detection technique used to quantify protein movement rates within the cell. This method exposes a small portion of the cell to an intense laser beam. The laser beam causes permanent photobleaching of the fluorophore-tagged proteins in the exposed region. As the bleached...
01:25Aquaporins
Aquaporins or AQPs are a family of integral membrane proteins whose primary function is to transport water, while some called aquaglyceroporins also transport glycerol. In addition, aquaporins have also been suspected to be involved in transporting volatile substances, such as carbon dioxide and ammonia, across membranes. Such AQPs that act as gas channels are often highly expressed in cells involved in the gaseous exchange, such as red blood cells, epithelial cells, and pulmonary capillaries.
01:22Protein Folding
Overview