At typical GATC sites elsewhere in the genome, remethylation begins immediately (1.5 minutes) following replication.

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The second component of the replicon model is the initiator protein.

This protein specifically recognizes a DNA element in the replicator and activates the initiation of replication

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AT base pairs called the DNA unwinding element (DUE).

IHF (integration host factor) and FIS (factor for inversion stimulation). These two proteins were discovered as required components of certain recombination reactions.

Another DNA-binding protein, HU (a histone like bacterial protein originally dubbed factor U), also participates but does not have a specific binding site.

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The single replicator 245 bp required for E. coli chromosomal replication is called oriC. Two repeated motifs are critical for oriC function.

The 9-mer motif is the binding site for the E. coli initiator, DnaA, and is repeated five times at oriC.

The 13-mer motif, repeated three times, is the initial site of ssDNA formation during initiation.

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oriC also contains 11 GATC/CTAG repeats that are methylated on adenine on both strands.