Interaction of the IciA protein with AT-rich regions in plasmid replication origins.
A set of AT-rich repeats is a common motif in prokaryotic replication origins. We have screened for proteins binding to the AT-rich repeat region in plasmids F, R1 and pSC101 using an electrophoretic mobility shift assay with PCR-amplified DNA fragments from the origins. The IciA protein, which is known to bind to the AT-rich repeat region in the Escherichia coli origin of chromosome replication, oriC, was found to bind to the corresponding region from plasmids F (oriS) and R1, but not to pSC101. DNase I footprint analysis showed that IciA interacted with the AT-rich region in both F and R1. When the IciA gene was deleted, the copy number of plasmid F increased somewhat, whereas there was no major effect on the replication of pSC101 and R1, or on the E. coli chromosome.
Wei
T
T
Department of Microbiology, Biomedical Center, Uppsala University, Sweden.
Bernander
R
R
D001426:Bacterial Proteins / Q000378:metabolism*; D001482:Base Composition; D001483:Base Sequence; D001665:Binding Sites; D004261:DNA Replication; D004269:DNA, Bacterial / Q000737:chemistry / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000378:metabolism*; D003850:Deoxyribonuclease I; D004926:Escherichia coli / Q000235:genetics*; D029968:Escherichia coli Proteins; D017353:Gene Deletion; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D010957:Plasmids; D016133:Polymerase Chain Reaction; D012091:Repetitive Sequences, Nucleic Acid
D001426:Bacterial Proteins; D004269:DNA, Bacterial; D004268:DNA-Binding Proteins; D029968:Escherichia coli Proteins; C068863:argP protein, E coli; D003850:Deoxyribonuclease I