A single DnaA box is sufficient for initiation from the P1 plasmid origin.
The P1 plasmid replication origin requires the host DnaA protein for function. Two DnaA-binding boxes lie in tandem within the previously defined minimal origin, constituting its left boundary. Three more boxes lie 200 base pairs to the right of these, in the leader region for the P1 repA gene. We show that either set alone is active for origin function. One of the two origin boxes is relatively inactive. Constructs with just one of the five boxes are active for specific origin function as long as the box conforms exactly to the published consensus. This single consensus box is functional when placed either to the left or right of the core origin sequences. The flexibility shown by this system suggests that the boxes play a role different from those in the host oriC origin, where the number and position of boxes are critical.
Abeles
A L
AL
Laboratory of Chromosome Biology, National Cancer Institute-Frederick Cancer Research and Development Center, Maryland 21701.
Reaves
L D
LD
Austin
S J
SJ
D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D002872:Chromosome Deletion; D003001:Cloning, Molecular; D004261:DNA Replication; D004926:Escherichia coli / Q000235:genetics* / Q000378:metabolism; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D009154:Mutation; D015345:Oligonucleotide Probes; D010957:Plasmids; D015183:Restriction Mapping
D001426:Bacterial Proteins; D015345:Oligonucleotide Probes