title: Isolation of Hfr strains from R+ and ColV2+ strains of Escherichia coli and derivation of an R'lac factor by transduction.
abstract: Temperature-resistant revertants were isolated from Escherichia coli strains carrying a temperature-sensitive dnaA mutation (initiation of chromosome replication) and either a repressed or a derepressed F-like R factor or a ColV2 factor. Many of the revertants had all the properties of Hfr strains, with a variety of directions and origins of transfer. From one such revertant, episomes carrying the R factor and part of the lac region (R'lac) could be isolated by transduction. This system offers a good selection for Hfr strains produced by integration of various episomes and for the isolation of R' factors.
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D002874:Chromosome Mapping; D003087:Colicins / Q000096:biosynthesis*; D004261:DNA Replication; D004269:DNA, Bacterial / Q000096:biosynthesis; D004352:Drug Resistance, Microbial; D004926:Escherichia coli / Q000187:drug effects / Q000302:isolation & purification* / Q000378:metabolism; D005809:Genes, Regulator; D009154:Mutation; D013489:Suppression, Genetic; D013696:Temperature; D014161:Transduction, Genetic
chemical_list: D000900:Anti-Bacterial Agents; D003087:Colicins; D004269:DNA, Bacterial