STRUCTURE AND REPLICATION OF DNA

我们的主要目标是获得有关噬菌体和 细菌DNA复制。这样的研究对最终的 了解DNA在正常和异常生长、病毒行为中的功能 和诱变。我们的研究利用了物理、生物化学和遗传 以物理化学和电子显微镜为重点的技术 方法论。我们希望确定为什么一些复制者使用一种 DNA复制的双向模式，其他单向复制和 还有一些人改变了他们的复制模式。进化的压力是什么 支持这些不同的DNA复制策略？DNA片段 负责启动DNA复制的因素将被研究 更详细地说。我们希望找出这到底是什么属性 必须有重要的序列才能在功能上起作用。能 其他序列在不寻常的情况下会发挥这样的作用吗？小调 目的是继续研究DNA螺旋的稳定性。我们希望有一个 更准确地了解A+T或 相邻DNA序列上富含G+C的片段。研究也将是 继续学习更多关于噬菌体内部结构的知识。我们的 调查将在很大程度上依赖电子显微镜方法和 为此，我们希望在这一领域开发新的技术，并扩大 电子显微镜部分变性图谱的有用性。一 直接感兴趣的技术是开发一种能够 自动DNA长度测量。

Our major aim is to obtain new information about bacteriophage and bacterial DNA replication. Such studies are fundamental to the eventual understanding of DNA function in normal and abnormal growth, virus behavior and mutagenesis. Our studies utilize physical, biochemical and genetic techniques with major emphasis on physicochemical and electron microscopic methodology. We wish to determine why some replicators employ a bidirectional mode of DNA replication, other replicate unidirectionally and yet others switch their mode of replication. What evolutionary pressures favored these various strategies for DNA duplication? The segment of DNA that is responsible for the initiation of DNA replication will be studied in greater detail. We wish to find out exactly what properties this very important sequence has to have in order to be functionally active. Can other sequences take on such a function under unusual conditions? Minor aims are to continue studies on DNA helical stability. We wish to have more accurate understanding of the magnitude of effects produced by A+T or G+C rich segments on neighboring DNA sequences. Studies will also be continued on learning more about internal structure of bacteriophage. Our investigations will rely heavily on electron microscopic methods and to this end we wish to develop new techniques in this area and to extend the usefulness of electron microscopic partial denaturation mapping. One technique of immediate interest is development of a system capable of automatic DNA length measurement.