Replication of the Bacterial Chromosome: Location of New Initiation Sites After Irradiation
Replication of the Bacterial Chromosome: Location of New Initiation Sites After Irradiation
复制标题
细菌染色体的复制：辐射后新起始位点的位置
DOI：
10.1128/jb.97.3.1169-1175.1969
复制
发表时间：
1969
影响因子：
3.2
通讯作者：
D. Billen
中科院分区：
文献类型：
--
作者：
D. Billen
辐照大肠杆菌后，沿细菌染色体沿着观察到新的复制位点。据证实，在X射线照射后，新的起始位点是随机的相对于固定的起源，而在紫外线照射后，它是选择性的，似乎是从固定的起源。结果表明，E.在大肠杆菌中，脱氧核糖核酸复制开始的新起始位点在染色体区域被诱导，而不限于固定起点。紫外光照射后，新的起始位点优先来自固定的起点。在这些研究中，氨基酸饥饿用于同步染色体复制，并允许染色体起点和末端的差异放射性同位素标记。为了便于解释，将活跃复制其染色体的生长细胞与照射时缺乏生长点的细胞进行比较。这些新的复制位点在观察到的脱氧核糖核酸复制后的X射线或紫外线曝光的动力学的作用进行了讨论。
New loci of replication along the bacterial chromosome are observed after irradiation of Escherichia coli. It was conjectured that, after X-irradiation, the new initiation site was random with respect to the fixed-origin, whereas, after ultraviolet light exposure, it was selective and appeared to be from the fixed-origin. Evidence presented here shows that, after X-irradiation of E. coli, the new initiation site(s) for the onset of deoxyribonucleic acid replication is induced at chromosomal regions not restricted to the fixed-origin. After ultraviolet light exposure, the new initiation site is preferentially from the fixed-origin. In these studies amino acid starvation was used to synchronize chromosome replication and to allow for differential radioisotopic labeling of the chromosomal origin and terminus. To facilitate interpretation, growing cells actively replicating their chromosome were compared with cells lacking growth points at the time of irradiation. The role of these new replication sites in the observed kinetics of deoxyribonucleic acid replication following X-ray or ultraviolet light exposure is discussed.