在ClC-ec1的分离离子结合和质子合的分子基础
Tao Jiang1, Wei Han1, Merritt Maduke2
1Department of Biochemistry, Center for Biophysics and Computational Biology, and Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign , Champaign, Illinois 61801, United States.
Journal of the American Chemical Society
|February 17, 2016
概括
/质子 (Cl/H+) 运输器使用不同的离子结合机制来调节质子运输. 不同的离子,如化物或酸盐, 破坏了对质子转移至关重要的水线,
科学领域:
- 分子生物学
- 生物化学
- 膜运输
背景情况:
- /质子 (Cl/H+) 载体是促进离子交换的关键膜蛋白.
- CLC超级家族调解了Cl和H+的合运输,但确切的机制,特别是离子依赖的H+合,仍然不清楚.
- 之前的研究强调了 ClC-ec1 中央离子结合点 (Scen) 对于 H+ 运输的重要作用.
研究的目的:
- 阐明离子结合的结构基础及其对ClC-ec1转运器中的H+运输的影响.
- 研究不同离子 (Cl,F,NO3,SCN) 如何与Scen区域相互作用并影响水线形成.
主要方法:
- 与各种离子 (Cl,F,NO3,SCN) 复合的ClC-ec1的结构分析.
- 在Scen地点调查离子结合协调和水合状态.
- 在GluiN和GluiX位点之间进行质子转移所需的短暂水线形成的评估.
主要成果:
- 在Scen部位观察到Cl,F,NO3和SCN的独特结合模式和水合模式.
- ClC-ec1形成连续水线的能力与不同的离子有显著差异.
- 虽然Cl促进了连续的水线,但F和NO3形成了伪水线,SCN完全废除了水线.
结论:
- 在Scen地点的离子结合决定了对质子运输至关重要的水线的形成.
- 差异性离子结合提供了一个解释CLC载体中不同离子的可变H+合的结构机制.
- 这些发现提供了对H+运输与非离子脱的原子层次见解.
更多相关视频
相关概念视频
Ion Exchange
1.5K
Ion exchange chromatography separates charged molecules from a solution by reversibly exchanging them with mobile, or 'active', ions associated with the oppositely charged stationary phase. This method can be used to separate ions, soften and deionize water, and purify solutions. The polymers comprising the ion-exchange column are high-molecular-weight and chemically stable polymers, crosslinked to be porous and essentially insoluble. They are also functionalized with either acidic or...
1.5K
Ion-Exchange Chromatography
2.8K
Ion-exchange chromatography, or IEC, is a technique for separating ions based on their affinity for the stationary phase. The stationary phase is a cross-linked polymer resin with covalently attached ionic functional groups. The functional groups can be either positively charged (cation exchangers) or negatively charged (anion exchangers). A cation exchanger consists of a polymeric anion and active cations, while an anion exchanger is a polymeric cation with active anions. The choice of...
2.8K
pH Regulation in Cells
8.1K
pH plays a critical role in maintaining normal cellular activities. It helps maintain the structure and function of various proteins, dictates the charge on cellular membranes, and is crucial for metabolic reactions inside the cell. Moreover, cells use the energy from the proton motive force to generate ATP.
Cytosolic pH
Under physiological conditions, the cytosolic pH is slightly more acidic than the extracellular pH. However, cells must prevent further acidification of their cytosol to...
Cytosolic pH
Under physiological conditions, the cytosolic pH is slightly more acidic than the extracellular pH. However, cells must prevent further acidification of their cytosol to...
8.1K
ATP Driven Pumps I: An Overview
10.4K
ATP-driven pumps, also known as transport ATPases, are integral membrane proteins. They have binding sites for ATP located on the membrane's cytosolic side and the ion-conducting domain in the transmembrane region. These pumps use the free energy released from ATP hydrolysis to move the solutes across cell membranes against an electrochemical gradient.
There are four main types of ATP-driven pumps - P-type, V-type, F-type, and ABC transporter. All these pumps are of varying complexities and...
There are four main types of ATP-driven pumps - P-type, V-type, F-type, and ABC transporter. All these pumps are of varying complexities and...
10.4K
Electrochemical Systems
69
Electrochemical systems provide a fascinating insight into the dynamic interplay of charged species within various phases. One notable example is the interaction between a membrane permeable to K⁺ ions but not to Cl⁻ ions, separating an aqueous KCl solution from pure water. As K⁺ ions diffuse through the membrane, they generate net charges on each phase, leading to a potential difference between them.Similarly, when a piece of Zn is immersed in an aqueous ZnSO₄ solution,...
69
Pore Transport and Ion-Pair Transport
1.5K
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...
1.5K


