title: A natural mutant of plasmid RP4 that confers phage resistance and reduced conjugative transfer.
abstract: A natural isolate of RP4 (PRC#116) acquired from the Stanford University Plasmid Reference Center differed from the wild-type Incompatibility Group P plasmid in several respects. Cells of Escherichia coli harboring PRC#116 were resistant to the IncP pili-specific bacteriophage PRD1 and GU5, and transferred this plasmid at a lower efficiency than the wild-type RP4. Phage sensitivity was restored, and transfer considerably improved in PRC#116+ bacteria transformed with plasmid constructs containing the origin of transfer (oriT region) of RP4. Mutant RP4 plasmids equivalent to PRC#116 were selected at a high frequency from an RP4+ E. coli population infected with PRD1 indicating that this RP4 variant may be the product of a very common mutation of the wild-type plasmid.
authors.affiliation: Sanitary Engineering and Environmental Health Research Laboratory, University of California, Berkeley.
authors.forename: L B
authors.initials: LB
authors.lastname: Kornstein
authors.forename: V L
authors.initials: VL
authors.lastname: Waters
authors.forename: R C
authors.initials: RC
authors.lastname: Cooper
mesh_terms: D001435:Bacteriophages / Q000502:physiology; D003227:Conjugation, Genetic; D004926:Escherichia coli / Q000235:genetics* / Q000648:ultrastructure; D008854:Microscopy, Electron; D009154:Mutation; D010641:Phenotype; D011815:R Factors / Q000235:genetics*; D014779:Virus Replication