毛细体对结晶动力学的影响:胰岛素
Ilya Reviakine1, Dimitra K Georgiou, Peter G Vekilov
1Department of Chemical Engineering, University of Houston, Houston, Texas 77204-4004, USA.
Journal of the American Chemical Society
|September 18, 2003
概括
毛细体控制了晶体层的产生,而二维毛细体长度 (L(c)) 影响了层增长率. 这项研究证实L(c) 在猪胰岛素结晶中的尺度增长步骤密度,较长的步骤独立于长度增长.
科学领域:
- 结晶科学 结晶科学
- 表面物理 表面物理
- 材料科学 材料科学 材料科学
背景情况:
- 毛细管对于层层的晶体生长至关重要,影响新层的产生.
- 理论模型将层边缘线张力和二维毛细血管长度 (L) 与层生成和增长率联系起来.
研究的目的:
- 调查二维毛细管长度 (L(c)) 与晶体生长过程中的层生成速度之间的相关性.
- 实验验证关于L (c) 在晶体生长动力学中的作用的理论预测.
主要方法:
- 在现场采用触摸模式原子力显微镜 (TM-AFM) 来研究晶体生长.
- 由于其合适的线性步骤生长动力学,研究了面 (R3) 猪胰岛素的结晶.
主要成果:
- 确定了二维毛细管长度 (L) 作为增长步骤密度的主要缩放因子.
- 比L长的步骤 (c) 呈现出仅仅依赖于超和的增长速度,独立于它们的长度.
- 测量了可与无机系统相比的动力系数,表明蛋白质结晶的超度很高.
结论:
- 实验证据支持L (c) 在缩放生长步骤密度方面的理论作用.
- 观察并解释了在高超和状态下步骤增长速度的理论偏差.
- 这项研究提供了对控制蛋白质晶体生长的基本机制的见解.
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