期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1973
卷号：70
期号：5
页码：1293-1297
DOI：10.1073/pnas.70.5.1293
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：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 CaCl2-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.
关键词：plasmid ; transformation ; antibiotic resistance ; DNA
