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Identification of a second promoter for the metY-nusA-infB operon of Escherichia coli.

ABSTRACT: The metY-nusA-infB operon of Escherichia coli encodes functions involved in both transcription and translation. Previous studies have identified a single promoter, P0, that directs transcription of the entire operon. We have identified a second promoter, P-1, that also is positioned to transcribe the complete operon. P-1 is located 50 base pairs upstream of and oriented in the same direction as P0. Sequences associated with P-1 have features suggestive of regulatory elements. P-1 differs from any previously described naturally occurring E. coli promoter by having -35 and -10 sequences that perfectly match the procaryotic promoter consensus hexamer sequences, although the spacing between the two elements is 1 base pair more than optimal. We demonstrate that P-1 is active in vivo.

SUBMITTER: Granston AE

PROVIDER: S-EPMC208867 | biostudies-other | 1990 May

REPOSITORIES: biostudies-other

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Identification of a second promoter for the metY-nusA-infB operon of Escherichia coli.

Granston A E AE Thompson D L DL Friedman D I DI

Journal of bacteriology 19900501 5

The metY-nusA-infB operon of Escherichia coli encodes functions involved in both transcription and translation. Previous studies have identified a single promoter, P0, that directs transcription of the entire operon. We have identified a second promoter, P-1, that also is positioned to transcribe the complete operon. P-1 is located 50 base pairs upstream of and oriented in the same direction as P0. Sequences associated with P-1 have features suggestive of regulatory elements. P-1 differs from an ...[more]

PMID: 1692017

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