Table 1.

Copy numbers of DnaA box plasmids

Growth mediumPlasmidDoubling time (min)No of copiesoriCa No. of copies/LSb
Glucose + Casamino AcidspTAC90934141.0
PFHC49634130.8
PFHC142534130.8
GlucosepTAC90972421.0
PFHC49674370.8
PFHC142574510.9
GlycerolpTAC90998431.0
PFHC496112571.1
PFHC1425116671.0
  • a Plasmid copy number per oriClocus was determined by Southern blotting as described in Materials and Methods.

  • b Relative plasmid copy number per unit of mass (LS = light scatter) was calculated from the number of copies peroriC locus and flow cytometry data on the number of origins per unit of light scatter. The data presented are relative to those of strain BBC119 carrying plasmid pTAC909 grown on the respective growth media.