The transcriptional repressor protein NsrR senses nitric oxide directly via a [2Fe-2S] cluster

Nick Tucker, Matthew G. Hicks, Thomas A. Clarke, Jason C. Crack, Govinda Chandra, Nick E. Le Brun, Ray Dixon, Matthew I. Hutchings

Research output: Contribution to journalArticlepeer-review

118 Citations (Scopus)
91 Downloads (Pure)


The regulatory protein NsrR, a member of the Rrf2 family of transcription repressors, is specifically dedicated to sensing nitric oxide ( NO) in a variety of pathogenic and non-pathogenic bacteria. It has been proposed that NO directly modulates NsrR activity by interacting with a predicted [Fe-S] cluster in the NsrR protein, but no experimental evidence has been published to support this hypothesis. Here we report the purification of NsrR from the obligate aerobe Streptomyces coelicolor. We demonstrate using UV-visible, near UV CD and EPR spectroscopy that the protein contains an NO-sensitive [2Fe-2S] cluster when purified from E. coli. Upon exposure of NsrR to NO, the cluster is nitrosylated, which results in the loss of DNA binding activity as detected by bandshift assays. Removal of the [2Fe-2S] cluster to generate apo-NsrR also resulted in loss of DNA binding activity. This is the first demonstration that NsrR contains an NO-sensitive [2Fe-2S] cluster that is required for DNA binding activity.
Original languageEnglish
Article numbere3623
Number of pages7
JournalPLoS One
Issue number11
Publication statusPublished - Nov 2008


  • biochemistry studies
  • nucleic acids
  • purines
  • pyrimidines
  • physiology
  • biochemistry of bacteria


Dive into the research topics of 'The transcriptional repressor protein NsrR senses nitric oxide directly via a [2Fe-2S] cluster'. Together they form a unique fingerprint.

Cite this