BACTERIOPHAGE P22 ESSENTIAL RECOMBINATION FUNCTION

广义遗传重组的机制进行的 噬菌体P22必需的重组功能（erf基因）将被 通过生物化学和遗传学的方法进行研究。 纯化Erf的相互作用 将通过凝胶电泳技术检查蛋白质与DNA， DNA状态的酶探针。 Erf蛋白的片段， 通过体外蛋白质水解和通过细胞中的链终止突变产生。 活的，将被净化。 它们的结构和DNA结合活性将 与完整的Erf平行检查。 abc基因，一种新的 发现P22重组相关基因，进行测序，并进行表达 通过基因工程技术在高水平上。 ABC蛋白将 纯化及其与DNA、Erf蛋白和可能的宿主细胞的相互作用 将检查重组功能。 Y的类似研究，另一个 新的重组相关基因P22，将进行。 电流变率相关 线性的、末端重复的P22染色体的超螺旋将被 检查以确定哪些噬菌体和宿主细胞组分是 这一过程所必需的。 我们将尝试在以下条件下分析这一过程： 体外，以允许ERF重组系统的重建 纯化的成分。 这样的重建将极大地促进 机制研究。 这项研究的长期目标是了解 基因重组。 净化是一个基本的 在遗传变异的产生中的重要性，在高等生物中， 免疫反应的多样性。

The mechanism of generalized genetic recombination carried out by the bacteriophage P22 essential recombination function (erf gene) will be studied by biochemical and genetic means. The interaction of purified Erf protein with DNA will be examined by gel electrophoretic techniques and enzymatic probes of the state of the DNA. Fragments of the Erf protein, generated by proteolysis in vitro and by chain terminating mutations in vivo, will be purified. Their structural and DNA binding activities will be examined in parallel with those of intact Erf. The abc gene, a newly discovered P22 recombination-related gene, will be sequenced, and expressed at high levels by genetic engineering techniques. The Abc protein will be purified and its interaction with DNA, Erf protein, and possibly, host cell recombination functions will be examined. Similar studies of Y, another new recombination-related gene of P22, will be carried out. erf-dependent supercoiling of linear, terminally repetitious P22 chromosomes will be examined in order to determine which phage and host cell components are necessary for this process. Attempts will be made to assay this process in vitro, in order to permit reconstruction of the erf recombination system from purified components. Such a reconstruction would greatly facilitate studies of mechanism. The long-term goal of this research is an understanding of the mechanisms of genetic recombination. Recombination is a process of fundamental importance in the generation of genetic variation and, in higher organisms, of diversity in the immune response.