Recircularization and Autonomous Replication of a Sheared R-Factor DNA Segment in Escherichia coli Transformants

作者：Stanley N. Cohen, Annie C. Y. Chang · 发表于：Proceedings of the National Academy of Sciences · 年份：1973 · DOI：10.1073/pnas.70.5.1293 · 被引用次数：196 · 研究领域：DNA Repair Mechanisms、Bacterial Genetics and Biotechnology、DNA and Nucleic Acid Chemistry

Controlled shearing of R-factor DNA leads to formation of fragments carrying an antibiotic resistance gene present on, but not expressed by, the intact R-factor. Transformation of CaCl(2)-treated E. coli by such fragments yields an autonomously replicating tetracycline-resistance plasmid (Tc6-5) that contains only a small fraction of the genome of the parent R-factor, and lacks both its fertility functions and its other drug-resistance determinants. Although the Tc6-5 plasmid is not self-transmissible, it can interact and/or recombine with conjugally-proficient plasmids that promote its transfer to other bacteria.