烷基化噬菌体T7感染的大肠杆菌B细胞中噬菌体T7 DNA合成的抑制机制

Mechanism of inhibition of bacteriophage T7 DNA synthesis in Escherichia coli B cells infected by alkylated bacteriophage T7.

作者信息

Czaika G, Mamet-Bratley M D, Karska-Wysocki B

出版信息

Mutat Res. 1986 Jul;166(1):1-8. doi: 10.1016/0167-8817(86)90034-9.

Abstract

Quantitative analysis of DNA replication, in E. coli B cells infected by methyl methanesulfonate-treated bacteriophage T7, showed that production of phage DNA was delayed and decreased. The cause of the delay appeared to be a delay in host-DNA breakdown, the process which provides nucleotides for phage-DNA synthesis. In addition, reutilisation of host-derived nucleotides was impaired. These observations can be accounted for by a model in which methyl groups on phage DNA slow down DNA injection and also reduce the replicational template activity of the DNA once it has entered the cell. Repair of alkylated phage DNA may be required not only for replication but also for normal injection of DNA.

摘要

对经甲磺酸甲酯处理的噬菌体T7感染的大肠杆菌B细胞中的DNA复制进行定量分析，结果表明噬菌体DNA的产生延迟且产量降低。延迟的原因似乎是宿主DNA降解延迟，而宿主DNA降解是为噬菌体DNA合成提供核苷酸的过程。此外，宿主来源核苷酸的再利用也受到损害。这些观察结果可以用一个模型来解释，即噬菌体DNA上的甲基减缓了DNA注入，并且一旦DNA进入细胞，还会降低其复制模板活性。烷基化噬菌体DNA的修复可能不仅对复制是必需的，对DNA的正常注入也是必需的。