Binding of a [2Fe-2S] cluster drives dimerization of ferric uptake regulator (Fur) in Escherichia coli.

ABSTRACT: The ferric uptake regulator (Fur) is a global transcription factor that reversibly binds an iron-sulfur [2Fe-2S] cluster via the cysteine residues (site 3) in response to elevation of intracellular free Fe content in Escherichia coli. Here, we report that when E. coli Fur is expressed in E. coli cells grown in M9 medium supplemented with Fe or zinc (Zn), purified Fur binds a [2Fe-2S] cluster or Zn(II), respectively. While apo-form Fur is a monomer and has no DNA-binding activity, both the [2Fe-2S] cluster-bound Fur and the Zn(II)-bound Fur are homodimers and have a similar binding activity for the DNA sequence known as the Fur-box. The inductively coupled mass spectrometry analyses show that the purified [2Fe-2S] cluster-bound Fur homodimer binds only one [2Fe-2S] cluster per monomer and n

SUBMITTER: Najafi F 

PROVIDER: S-EPMC12538065 | biostudies-literature | 2025 Sep

REPOSITORIES: biostudies-literature