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. 1996 May 15;24(10):1865–1872. doi: 10.1093/nar/24.10.1865

Interaction of the IciA protein with AT-rich regions in plasmid replication origins.

T Wei 1, R Bernander 1
PMCID: PMC145872  PMID: 8657567

Abstract

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.

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Selected References

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