Zygotic induction of plasmid ssb and psiB genes following conjugative transfer of Incl1 plasmid Collb-P9.
The Incl1 conjugative plasmid Collb-P9 carries a psiB gene that prevents induction of the SOS response in host bacteria. This locus is located 2.5 kb downstream of the ssb (single-stranded DNA-binding protein) gene in the leading region. This portion of Collb is strikingly similar to part of the leading region of the otherwise distinct F plasmid. Expression of psiB and ssb is increased when the host cell is exposed to an SOS-inducing treatment or the Collb transfer system is derepressed. Moreover, expression of both genes on a derepressed plasmid is strongly enhanced in conjugatively infected recipient cells. Carriage of the psiB gene by Collb is shown to prevent a low level of SOS induction following conjugation. Plasmid ssb and psiB genes may function to promote installation of the replicon in the new cell.
Jones
A L
AL
Department of Genetics, University of Leicester, UK.
Barth
P T
PT
Wilkins
B M
BM
D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics*; D001483:Base Sequence; D003001:Cloning, Molecular; D003227:Conjugation, Genetic / Q000502:physiology*; D004269:DNA, Bacterial / Q000528:radiation effects; D004268:DNA-Binding Proteins / Q000235:genetics*; D004926:Escherichia coli / Q000235:genetics*; D015964:Gene Expression Regulation, Bacterial / Q000502:physiology*; D006579:Heterozygote; D007763:Lac Operon; D008969:Molecular Sequence Data; D009154:Mutation; D010957:Plasmids; D015183:Restriction Mapping; D014466:Ultraviolet Rays
D001426:Bacterial Proteins; D004269:DNA, Bacterial; D004268:DNA-Binding Proteins; C058074:PsiB protein, Bacteria