PHYSICAL CHEMISTRY OF BACTERIAL VIRUSES

这个项目的长期目标是在物理化学方面理解 术语，细菌病毒是如何组装的。这些可能是最多的 复杂的超分子组件目前容易受到详细的 分子理解。因此，它们充当了 高等生物细胞器形态发生的调控。我们 专注于T4噬菌体，并在下一个项目期间拥有这些特定的 目的：1.确定底板蛋白gp48和gp54的作用方式 与基板相互作用，相互作用，与尾管蛋白相互作用 Gp19调节T4噬菌体尾管长度。2.确定 管状聚合的传播和终止机制 研究聚合动力学，寻找齐聚物 Gp19的中间产物及其是否发生构象变化 聚合时发生变化。3.确定两者之间的相似程度 化学和物理方面的尾部纤维和非肌肉肌球蛋白 结构、反应性和酶活性；以及寻找肌动蛋白样蛋白 T4中的蛋白质(gp63可能是其中之一)。4.确定其作用机制。 尾部纤维附着在基极上，阐明其结构， 能量学，与gp63和晶须形成的络合物的动力学。5. 确定稳定噬菌体衣壳内DNA的力量，特别是 使用聚电解质和分子间力的聚阳离子的作用 理论。为了实现这些目标，我们将制备噬菌体成分 合适的突变体，通过标准的生化技术进行纯化，以及 用化学和体外互补的方法进行检测。主要的体能 工具将是激光散射和流体动力学；但我们还将 使用电子显微镜、圆二色谱、化学交联剂和 蛋白质-蛋白质相互作用的各种测试。

The long-range goal of this project is to understand, in physical chemical terms, how bacterial viruses are assembled. These are perhaps the most complex supramolecular assemblies currently susceptible to detailed molecular understanding. As such they serve as realistic models for the regulation of morphogenesis of cell organelles in higher organisms. We concentrate on T4 phage, and in the next project period have these specific aims: 1. Determine the ways in which baseplate proteins gp48 and gp54 interact with the baseplate, with each other and with the tail tube protein gp19 to regulate the length of the tail tube of T4 phage. 2. Determine the propagation and termination mechanisms for tube polymerization, by investigating the kinetics of polymerization, searching for oligomeric intermediates of gp19 and determining whether it undergoes a conformational change upon polymerization. 3. Determine the extent of similarity between tail fibers and non-muscle myosin, with respect to chemical and physical structure, reactivity, and enzymatic activity; and search for actin-like proteins (of which gp63 may be one) in T4. 4. Determine the mechanism of attachment of tail fibers to basepolates, elucidating the structures, energetics, an dynamics of the complexes with gp63 and whiskers. 5. Determine the forces stabilizing DNA inside phage capsids, especially the role of polycations, using polyelectrolyte and intermolecular force theories. To accomplish these aims we shall prepare phage components from appropriate mutants, purify them by standard biochemical techniques, and assay both chemically and by in vitro complementation. The major physical tools will be laser light scattering and hydrodynamics; but we will also use electron microscopy, circular dichroism, chemical crosslinking, and various tests of protein-protein interaction.