甲基组动态作为蛋白质动态过渡的探测器
Joseph E Curtis1, Mounir Tarek, Douglas J Tobias
1NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA.
Journal of the American Chemical Society
|December 9, 2004
概括
化蛋白质在200K左右表现出关键的动态过渡.分子动力学模拟显示,溶剂对于这种蛋白质范围内的过渡至关重要,从玻璃状运动转变为液态运动.
科学领域:
- 生物物理学的生物物理.
- 蛋白质动力学 蛋白质动力学
- 分子模拟分子模拟
背景情况:
- 蛋白质表现出复杂的动态,对其功能至关重要.
- 从玻璃状运动到液体状运动的动态过渡发生在约200K的水合蛋白中.
- 了解这种过渡是蛋白质功能和稳定性的关键.
研究的目的:
- 为了研究蛋白质动态的温度依赖性.
- 量化不同蛋白质环境 (水合晶体,脱水粉末,水溶液) 的动态变化.
- 确定溶剂在蛋白质动态转换中的作用.
主要方法:
- 使用了分子动力学模拟.
- 这项研究的重点是核糖核酶A.
- 甲基原子的平均平方波动 (MSF) 在100 psi时间尺度上进行了分析.
主要成果:
- 在300 K的溶液中,MSFs显示出广泛的分布,与NMR数据保持一致.
- 水合晶MSF分布与溶液相似,但偏向较低;脱水导致显著转移到较低的值.
- 大多数水合蛋白中的甲基组表现出非线性温度依赖,过渡度接近200K,与脱水蛋白不同.
结论:
- 动态转换发生在大部分蛋白质中.
- 溶剂是这种蛋白质范围内的动态过渡的关键要求.
- 蛋白质动力学对水合水平和温度非常敏感.
相关概念视频
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Structural proteins are a category of proteins responsible for functions ranging from cell shape and movement to providing support to major structures such as bones, cartilage, hair, and muscles. This group includes proteins such as collagen, actin, myosin, and keratin.
Collagen, the most abundant protein in mammals, is found throughout the body. In connective tissue, such as skin, ligaments, and tendons, it provides tensile strength and elasticity. In bones and teeth, it mineralizes to form...
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