Repression of the Escherichia coli melR promoter by MelR: evidence that efficient repression requires the formation of a repression loop
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چکیده
منابع مشابه
Autoregulation of the Escherichia coli melR promoter: repression involves four molecules of MelR
The Escherichia coli MelR protein is a transcription activator that autoregulates its own promoter by repressing transcription initiation. Optimal repression requires MelR binding to a site that overlaps the melR transcription start point and to upstream sites. In this work, we have investigated the different determinants needed for optimal repression and their spatial requirements. We show tha...
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Transcription of the Escherichia coli melAB operon is regulated by the MelR protein, an AraC family member whose activity is modulated by the binding of melibiose. In the absence of melibiose, MelR is unable to activate the melAB promoter but autoregulates its own expression by repressing the melR promoter. Melibiose triggers MelR-dependent activation of the melAB promoter and relieves MelR-dep...
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ژورنال
عنوان ژورنال: Molecular Microbiology
سال: 2000
ISSN: 0950-382X,1365-2958
DOI: 10.1046/j.1365-2958.2000.01850.x