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Autoregulation of the Escherichia coli melR promoter: repression involves four molecules of MelR.

ABSTRACT: 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 that repression requires a complex involving four DNA-bound MelR molecules, and that the global CRP regulator plays little or no role.

SUBMITTER: Samarasinghe S

PROVIDER: S-EPMC2377442 | biostudies-literature | 2008 May

REPOSITORIES: biostudies-literature

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Autoregulation of the Escherichia coli melR promoter: repression involves four molecules of MelR.

Samarasinghe Shivanthi S El-Robh Mohamed Samir MS Grainger David C DC Zhang Wenke W Soultanas Panos P Busby Stephen J W SJ

Nucleic acids research 20080316 8

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 that repression requires a complex involving four DNA-bound MelR molecules, and that the global CRP regula ...[more]

PMID: 18346968

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