PHYSICS OF IONIC CHANNELS AND OTHER PROTEINS WITH AQUEOUS CAVITIES

离子通道和其他具有水腔的蛋白质的物理学

• 批准号: 3854566
• 负责人: V A PARSEGIAN
• 金额: --
• 依托单位: NATIONAL INSTITUTE OF DIABETES AND DIGESTIVE AND KIDNEY DISEASES
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/3854566
• 关键词: acidity /alkalinity; biological fluid transport; biophysics; body fluid osmolarity; cell osmotic pressure; cell water; chemical binding; conformation; granule; hemoglobin; laboratory mouse; ligands; mast cell; membrane channels; membrane reconstitution /synthesis; secretion; thermodynamics; voltage gated channel; water

Through the use of osmotic stress, it has been found that some 60 water molecules bind to hemoglobin when it switches from the "tense" deoxy to the "relaxed" oxy forms. It appears that this water should be treated as a liganding species much as oxygen or other allosteric effectors. The alpha-toxin trans-membrane channel from Staphylococcus aureus has been reconstituted into bilayer membranes and osmotically stressed to provide the information that 600 water molecules enter and leave this channel when it opens and closes under applied voltage. This channel appears also to have different pH sensitivity from each side of the membrane. Swelling of secretory granules after release from beige mouse mast cells appears to be governed by hydration/dehydration events that can be described by thermodynamic analysis similar to that developed to analyze macromolecular assembly in vitro. The coupling of swelling concomitant to secretion with the exchange of counterions to the polysaccharide matrix suggests a further parallel between in vivo and in vitro processes.

通过使用渗透胁迫，已经发现，大约60 当血红蛋白从“紧张”状态转换时， 脱氧到“放松的”氧形式。 看来这水应该是 被视为配体物质，就像氧气或其他变构物质一样 效应器 金黄色葡萄球菌的α毒素跨膜通道 重组成双层膜，并进行热应力处理， 提供了600个水分子进入和离开这个 当它在施加电压下打开和关闭时，通道。 这个频道 似乎也有不同的pH敏感性，从每一侧的 膜的 米色小鼠肥大细胞释放后分泌颗粒的肿胀 似乎是由水合/脱水事件控制的， 通过热力学分析描述，类似于开发的热力学分析， 分析体外大分子组装。 溶胀耦合 伴随着分泌的反离子交换， 多糖基质表明体内和 体外过程。