Non-chromosomal antibiotic resistance in bacteria. 3. Isolation of the discrete transfer unit of the R-factor R1.
نویسندگان
چکیده
A covalently-closed circular DNA species, banding at a buoyant density of rho = 1.709 g/cm(3) in CsCl, has been identified in antibiotic-sensitive colonies of E. coli strain AB2463 (rec A(-)) after mating with a Proteus mirabilis strain that carries the R-factor, R1. This plasmid, which represents a stable segregant of R1 that has lost all of the drug resistance determinants present on the parent R-factor but which has retained its ability to be transferred by conjugation, fulfills the functional definition of the R-factor transfer unit (RTF).
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عنوان ژورنال:
- Proceedings of the National Academy of Sciences of the United States of America
دوره 67 2 شماره
صفحات -
تاریخ انتشار 1970