'WET' ELECTROSTATICS AND BIOMOLECULAR SELF-ASSEMBLY

“湿”静电和生物分子自组装

• 批准号: 8169973
• 负责人: GERARD C WONG
• 金额: $ 0.64万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-05-01 至 2011-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8169973
• 关键词: Bacteria; Behavior; Biopolymers; Capsid; Charge; Chromosomes; Complex; Computer Retrieval of Information on Scientific Projects Database; DNA; DNA Packaging; Electrostatics; Exhibits; F-Actin; Funding; Genetic Engineering; Grant; Histones; Institution; Intuition; Ions; Lactoferrin; Membrane; Molecular; Muramidase; Physical condensation; Protamines; Proteins; Research; Research Personnel; Resources; Salts; Series; Solutions; Source; Techniques; United States National Institutes of Health; Viral; Work; aqueous; globular protein; macromolecule; mutant; programs; retinal rods; self assembly; theories

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. 'Wet' electrostatic interactions are poorly understood and often exhibit counterintuitive behavior. For example, two like-charged macromolecules in aqueous solution are expected to repel one another, which is essentially the prediction of prevailing mean-field theories. In the presence of multivalent ions, however, many biopolymers actually attract one another and condense into compact, ordered states. Examples include DNA condensation by charged histones in chromosomes, and DNA packaging by multivalent protamines in bacteria and viral capsids. In our previous work at SSRL, we have directly observed a molecular mechanism for attractions between rod-like polyelectrolytes by observing counterion organization. The aim of the present proposed program is to develop our intuition for more complex forms of electrostatic assembly. We will examine a series of paradigmatic examples of interactions between simple geometric objects, such as complexes formed between like-charged rods and sheets (anionic DNA and anionic membranes), or complexes formed between oppositely charged rods and spheroids (F-actin and monodisperse cationic globular proteins (lysozyme, lactoferrin)) in the presence of salts of different valence. In particular, we will take advantage of genetic engineering techniques to make mutant proteins with essentially the same size but with different net charges and charge distributions, and examine how these changes impinge on their self-assembly behavior.

该副本是利用众多研究子项目之一 由NIH/NCRR资助的中心赠款提供的资源。子弹和 调查员（PI）可能已经从其他NIH来源获得了主要资金， 因此，可以在其他清晰的条目中表示。列出的机构是 对于中心，这不一定是调查员的机构。 “湿”静电相互作用知之甚少，并且经常表现出违反直觉的行为。例如，预期水溶液中的两个类似的大分子将相互排斥，这本质上是对现行平均场理论的预测。然而，在存在多价离子的情况下，许多生物聚合物实际上彼此吸引并凝结成紧凑的有序状态。例子包括染色体中带电的组蛋白的DNA缩合，以及细菌和病毒式衣壳中多价蛋白质的DNA包装。在我们以前在SSRL的工作中，我们直接观察到一种分子机制，可以通过观察抗衡离子组织来观察棒状聚电解质之间的景点。本提议的计划的目的是开发我们的直觉，以更复杂的静电组件形式。我们将研究简单几何对象之间相互作用的一系列范式示例，例如类似的杆和板之间形成的复合物（阴离子DNA和阴离子膜），或在相反电荷的杆和球形之间形成的复合物（f-肌动蛋白和单肌蛋白酶阳离子阳离子阳离子阳离子阳离子，在存在不同价盐的情况下，球状蛋白（溶菌酶，乳铁蛋白））。特别是，我们将利用基因工程技术来制造具有基本相同大小但净电荷和电荷分布的突变蛋白，并研究这些变化如何影响其自组装行为。