Identification of a second promoter for the metY-nusA-infB operon of Escherichia coli.
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.
Granston
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Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor 48109.
Thompson
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Friedman
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D001483:Base Sequence; D004269:DNA, Bacterial / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics*; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D015345:Oligonucleotide Probes; D009876:Operon; D010957:Plasmids; D011401:Promoter Regions, Genetic; D014176:Protein Biosynthesis; D012329:RNA, Bacterial / Q000235:genetics / Q000302:isolation & purification; D012045:Regulatory Sequences, Nucleic Acid; D014158:Transcription, Genetic
D004269:DNA, Bacterial; D015345:Oligonucleotide Probes; D012329:RNA, Bacterial