从异常的X射线衍射和分子动力学模拟中对OmpF蛋白中离子透的结构研究
Balasundaresan Dhakshnamoorthy1, Brigitte K Ziervogel1, Lydia Blachowicz1
1Department of Biochemistry and Molecular Biology, Gordon Center for Integrative Science, University of Chicago Chicago, IL 60637, USA.
Journal of the American Chemical Society
|October 11, 2013
概括
使用X射线散射和模拟,绘制了OmpF porin通道中的阴离子和阴离子结合位. 这揭示了离子转移的独特途径,解释了OmpF的体.
科学领域:
- 生物物理学的生物物理.
- 结构生物学 结构生物学
- 分子生物学分子生物学
背景情况:
- 来自大肠杆菌的OmpF孔是研究水性分子孔内的静电相互作用的模型系统.
- 了解海豚中的离子运输机制对于各种生物过程至关重要.
研究的目的:
- 在OmpF孔内绘制有利的离子和离子位置.
- 在OmpF通道上阐明完整的阴离子和离子转移路径.
- 为了深入了解控制OmpF中离子选择性的分子机制.
主要方法:
- 来自四个晶体结构的离子 (Br) 的异常X射线散射.
- 与之前确定的 (Mg2+) 和 (Rb+) 离子位点进行比较.
- 分子动力学模拟以补充实验数据.
主要成果:
- 阳离子在整个OmpF孔径长度内以离散集群结合.
- 电离子在细胞外,表面暴露的循环上的保存结合点中被发现.
- 分子动力学模拟与实验发现保持一致,并确定离子相互作用的关键残留物.
结论:
- 这项研究提供了一个关于OmpF孔内的离子转移通路的全面图片.
- 对离子和离子的明显结合模式有助于OmpF孔的离子选择性.
- 鉴定到的关键残留物为了解和潜在地操纵毛孔功能提供了目标.
更多相关视频
08:55Single-Molecule Imaging of Lateral Mobility and Ion Channel Activity in Lipid Bilayers using Total Internal Reflection Fluorescence TIRF Microscopy
Published on: February 17, 2023
4.4K
11:55Membrane Transport Processes Analyzed by a Highly Parallel Nanopore Chip System at Single Protein Resolution
Published on: August 16, 2016
11.4K
相关概念视频
Structure of Porins
3.1K
Mitochondria, chloroplasts, and gram-negative bacteria have transmembrane, beta-barrel proteins called porins to mediate the free diffusion of ions and metabolites across the membrane. Mitochondrial porin precursors contain conserved amino acid sequences called beta signals at their C-terminal. Beta signals have a motif of PoXGXXHyXHy (Po-Polar, X-Any amino acid, G-Glycine, Hy-LargeHydrophobic), which are crucial for precursor recognition to initiate precursor assembly. Beta-barrel...
3.1K
Pore Transport and Ion-Pair Transport
1.6K
Pore transport and ion-pair formation are critical mechanisms for the absorption and distribution of drugs in the body.
Pore transport, also known as convective transport, is a process where small molecules like urea, water, and sugars rapidly cross cell membranes as though there were channels or pores in the membrane. Although direct microscopic evidence is limited but the concept of pores or channels is widely accepted based on physiological evidence. Despite the lack of direct...
Pore transport, also known as convective transport, is a process where small molecules like urea, water, and sugars rapidly cross cell membranes as though there were channels or pores in the membrane. Although direct microscopic evidence is limited but the concept of pores or channels is widely accepted based on physiological evidence. Despite the lack of direct...
1.6K
Porin Insertion in the Outer Mitochondrial Membrane
4.6K
Porins are beta-barrel proteins translocated to the mitochondrial outer membrane through the TOM complex into the intermembrane space. Porin precursors bind TIM chaperones within the intermembrane space and are guided to the Sorting and Assembly Machinery complex or SAM complex on the outer mitochondrial membrane.
Three models describe the assembly of porins by the SAM complex and their insertion into the outer membrane. Model 1 suggests that porins are assembled outside the SAM channel as the...
Three models describe the assembly of porins by the SAM complex and their insertion into the outer membrane. Model 1 suggests that porins are assembled outside the SAM channel as the...
4.6K
Aquaporins
5.1K
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.
5.1K
