在高度排序的脂质双层中,玻璃状动态的特征出现了软动态通道
Harini SureshKumar1, Sahithya S Iyer2, Atreyee Banerjee3,4
1Molecular Biophysics Unit, Indian Institute of Science, Bangalore, KA 560012, India.
The Journal of chemical physics
|April 8, 2025
概括
生物膜表现出复杂的空间和动态异质性. 模拟显示,在有序的脂质双层内存在"软流体通道",这表明类似玻璃的动力学可能为生物功能促进分子相互作用.
科学领域:
- 生物物理学的生物物理.
- 计算生物学 计算生物学
- 材料科学 材料科学 材料科学
背景情况:
- 研究生物脂质膜的空间和动态异质性至关重要,但由于时间和长度尺度的实验限制,这是具有挑战性的.
- 分子模拟为膜异质性及其功能影响的起源提供了宝贵的见解.
- 非亲缘位移 (NAD) 框架是从颗粒物质物理学中改编的,它提供了一种分析模拟膜中的分子级秩序的方法.
研究的目的:
- 将NAD框架应用于异质脂质双层的全原子模拟,以表征空间和时间组织.
- 研究大规模液体有序膜斑块中的温度依赖的动态和横向组织.
- 使用已建立的玻璃物理标记物量化动态异质性.
主要方法:
- 在微秒时间尺度上利用DPPC/DOPC/CHOL脂质双层 (0.55:0.15:0.30组成) 的全原子分子动力学模拟.
- 应用非亲缘位移 (NAD) 框架来分析局部膜秩序和动态异质性.
- 采用经典的玻璃物理指标,包括重叠,四点易感性,范霍夫和中间散射函数,以描述脂质动态.
主要成果:
- 模拟的大双层斑块 (40 × 40 nm2) 显示出显著的动态异质性,即使在液体有序阶段.
- 在NAD分析中,在密集的膜内发现了"软流体通道",类似于形成玻璃的二元混合物.
- 使用玻璃物理标记物的量化证实了类似玻璃的动力学和控制脂质运动的多个时间尺度.
结论:
- 高度排序的生物膜系统可以表现出复杂的,类似玻璃的动态.
- 在有序的膜内发现的软流体通道可以作为分子相遇的功能导管.
- 这些发现表明,在脂质纳米领域和木中,有促进生物功能的机制.
相关概念视频
01:35Asymmetric Lipid Bilayer
7.0K
Biological membranes show uneven distribution of different types of lipids in the inner and outer layers, resulting in transverse asymmetric membranes. The treatment of the erythrocyte membrane with the enzyme phospholipase confirmed the asymmetric nature of the lipid bilayer. The enzyme hydrolyzes lipids into fatty acids and hydrophilic groups. The phospholipase acts only on the outer layer of the membrane, while the inner layer remains intact. The phospholipase treatment resulted in 80%...
7.0K
01:19Fluid Mosaic Model
11.2K
Scientists identified the plasma membrane in the 1890s and its principal chemical components (lipids and proteins) by 1915. The model for plasma membrane structure, proposed in 1935 by Hugh Davson and James Danielli, was the first model to be widely accepted in the scientific community. The model was based on the plasma membrane's "railroad track" appearance in early electron micrographs. Davson and Danielli theorized that the plasma membrane's structure resembled a sandwich...
11.2K
01:26Membrane Fluidity
10.7K
Membrane fluidity is explained by the fluid mosaic model of the cell membrane, which describes the plasma membrane structure as a mosaic of components—including phospholipids, cholesterol, proteins, and carbohydrates—that gives the membrane a fluid character.
Mosaic nature of the membrane
The mosaic characteristic of the membrane helps the plasma membrane remain fluid. The integral proteins and lipids exist as separate but loosely-attached molecules in the membrane. The membrane is...
Mosaic nature of the membrane
The mosaic characteristic of the membrane helps the plasma membrane remain fluid. The integral proteins and lipids exist as separate but loosely-attached molecules in the membrane. The membrane is...
10.7K