From BioE80 Boot
Jump to: navigation, search

Author Information

Sabar Dasgupta

Basic Information

  • ID: EG10359
  • Name: fur
  • Organism: E. coli
  • Description: The fur gene expresses the ferric uptake regulator protein (Fur) and is the "founding member" of a family of proteins that regulate uptake and homeostasis of various metal ions. The Fur protein regulates the concentration of iron—an essential function. According to Uniprot, this protein regulates iron levels by sequence-specific DNA binding, meaning that the Fur protein selectively binds to DNA and prevents transcription of genes that cause iron uptake. However, when iron concentrations are low, the Fur protein undergoes a conformational change and can no longer bind to DNA to prevent transcription (Wikipedia). Furthermore, in E. coli, the Fur protein is not only involved in iron concentration regulation, but also can bind zinc to undergo conformational change and "regulates the expression of several outer-membrane proteins", not just the iron transport operon (UniProt).
  • DNA Length: 447 base pairs.
  • DNA sequence:


  • Amino Acid length: 148 amino acids.
  • Amino Acid sequence:


Function and Homologs

  • Product: Ferric uptake regulation protein
  • Module: DNA-binding, Iron transport operon regulation/repression.
  • Closest homologous proteins: The top (max three) homologous proteins to this protein, as identified by BLAST searches.
    • ferric iron uptake transcriptional regulator [Escherichia, 303/100%/1e-104/99% WP_069915419.1
    • ferric iron uptake transcriptional regulator [Escherichia albertii], 303/100%/2e-104/99% WP_059238291.1
    • transcriptional repressor [Escherichia, 303/100%/2e-104/99% WP_000131708.1


  • Expression Level: high
  • Expression Level Hypothesis: Regulation of iron levels will require a large number of proteins if iron uptake is being inhibited. It is possible that the E. coli proteome was measured in an environment with low iron levels.
  • Expression Level References and Description: 10748 proteins per cell E. coli proteome.
  • Expression Time: At which time should the gene be expressed in the lifecycle of our organism? Early
  • Expression Level Hypothesis: If this gene is not expressed relatively early, then iron levels will not be able to be regulated effectively.
  • Expression Time References and Description: Uniprot. According to WikiGenes, the protein expressed by this gene is versatile and plays a role in homeostasis beyond just iron regulation.

Gene Context

  • Other Components: There are other components to this family (Manganese uptake regulator (Mur), Nickel uptake regulator (Nur), peroxide regulator (PerR), and Zinc uptake regulator (Zur)) in other species, but none of these genes were found in the E. Coli databases.
  • Possible Dependencies: The presence (or lack) of Fe2+ is the main dependency of this gene, but this gene actually regulates itself, so there aren't other genes working directly to regulate iron in the same way. You could count the DNA itself as a trivial dependency.
  • Process: Fur-Fe2+ DNA-binding transcriptional dual regulation
    • Inputs: Fur, Fe2+
    • Outputs: Fur-Fe2+, DNA-binding