微粒密度通过蛋白质二次结构的可逆切换来调节
Rory E Sallach1, Min Wei, Nilanjana Biswas
1Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, USA.
Journal of the American Chemical Society
|September 7, 2006
概括
研究人员设计了智能蛋白质,其尺寸和密度随温度变化. 这种蛋白质折叠过渡为刺激响应药物递送系统提供了一种新方法.
科学领域:
- 生物材料科学 生物材料科学
- 聚合物化学 聚合物化学
- 蛋白质工程是指蛋白质工程.
背景情况:
- 蛋白质的二次结构可以经历可逆的,突然的转变.
- 这种过渡可以用来设计响应性材料.
- 两性蛋白质共聚合物提供了自我组装成纳米结构的潜力.
研究的目的:
- 使用弹性素模拟性序列设计和表征一个"智能"蛋白质细胞系统.
- 为了研究温度诱导的蛋白质折叠对菌根性质的影响.
- 建立一种对刺激反应药物递送车辆的新机制.
主要方法:
- 利用重组DNA方法制备一个蛋白质triblock共聚合物.
- 在低于和高于逆转换温度 (Tt) 的稀释溶液中研究了微粒形成和性质.
- 使用生物物理技术分析了小胞密度和大小的变化.
主要成果:
- 开发的两性蛋白质triblock共聚合物,在Tt以下形成单分散小粒 (~100 nm R(H)).
- 观察到小内部密度的急剧增加和Tt以上的尺寸缩小.
- 证明结构变化是由螺旋到片状蛋白质折叠过渡驱动的.
结论:
- 蛋白质的二次结构转换可以被可控地利用来设计"智能"的细胞系统.
- 温度诱导的蛋白质折叠可逆地改变了细胞的紧性和大小.
- 这些以蛋白质聚合物为基础的菌体代表了先进药物输送应用的新平台.
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