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Published on: November 1, 2012
Expression of the seqA gene is negatively modulated by the HU protein in Escherichia coli
1Institute for Molecular Biology and Genetics, School of Biological Sciences, Seoul National University, Korea.
Abstract:
The SeqA protein acts as a regulator of chromosomal replication initiation in Escherichia coli by sequestering hemi-methylated oriC, effectively blocking methylation and therefore preventing rapid re-initiation. The level of SeqA protein is maximal at mid-log phase and decreases when cells enter late-log phase. In hup mutants that lack the HU protein, the maximal seqA expression is also seen at mid-log phase, but seqA expression, as well as SeqA levels and activity, is increased by up to four fold relative to that in the wild type. These results suggest that the HU protein functions as a negative modulator of seqA expression.
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