title: dnaB gene of Escherichia coli K-12 affects superinfection inhibition between F' plasmids.
abstract: F' Escherichia coli K-12 strains bearing the chromosomal mutation dnaB43 offer significantly less resistance to the conjugational introduction of a second F' plasmid than do nonmutant strains. Both the entry exclusion and incompatibility components of superinfection inhibition are altered. This action of dnaB43 occurs regardless of the presence of a recA-minus mutation in matings in liquid cultures and on membrane filters and is not limited to a particular set of F' plasmids. These effects are co-transducible by phage P1 with the temperature sensitivity conferred by dnaB43. The effects also occur with a strain carrying dnaB107. In the double F' strains that arise, the two plasmids exist as units autonomous of one another and the chromosome.
mesh_terms: D002876:Chromosomes, Bacterial / Q000378:metabolism; D003090:Coliphages / Q000378:metabolism; D003227:Conjugation, Genetic; D004269:DNA, Bacterial / Q000378:metabolism*; D004926:Escherichia coli / Q000378:metabolism*; D005111:Extrachromosomal Inheritance; D005144:F Factor; D005796:Genes; D009154:Mutation; D010957:Plasmids; D014161:Transduction, Genetic
chemical_list: D004269:DNA, Bacterial