Regulation of transcription of genes required for fatty acid transport and unsaturated fatty acid biosynthesis in Escherichiacoli by FadR

Concetta O. DiRusso, Amy K. Metzger, Tamra L. Heimert

Research output: Contribution to journalArticlepeer-review

65 Scopus citations

Abstract

Fatty acid biosynthesis and fatty acid degradation in Escherichiacoliare co‐ordinately regulated at the level of transcription by the product of the fadRgene, FadR. In the present work we investigate FadR interaction with the fabA and fadL promoters. The FadR‐responsive operator within fabA, OA, was localized to a region −47 to −31 base pairs relative to the start of transcription using DNase I protection studies. The promoter and untranslated leader within fadL had two binding sites for FadR, OL1 at −25 to −9 and OL2 at −1 to +16 relative to the start of transcription. The binding affinity of FadR for OA and OL1 or OL2 was lower than that for the single site within fadB (OB) as measured using protein‐DNA gel retention assays. Overall, these experiments demonstrated that the affinity of FadR binding for DNA containing the fadB, fadL and fabA promoters was OB > OL1, OL2 > OA. We could not distinguish separate binding affinities for OL1 or OL2. We demonstrated repression of fadL transcription and activation of fabA transcription in vitro using run‐off transcription assays containing purified FadR and RNA polymerase.

Original languageEnglish (US)
Pages (from-to)311-322
Number of pages12
JournalMolecular Microbiology
Volume7
Issue number2
DOIs
StatePublished - Jan 1993
Externally publishedYes

ASJC Scopus subject areas

  • Microbiology
  • Molecular Biology

Fingerprint Dive into the research topics of 'Regulation of transcription of genes required for fatty acid transport and unsaturated fatty acid biosynthesis in Escherichiacoli by FadR'. Together they form a unique fingerprint.

Cite this