Fatty acid metabolism regulator protein FadR

Summary

In molecular biology, the fatty acid metabolism regulator protein FadR, is a bacterial transcription factor.

FadR C-terminal domain
fadr, fatty acid responsive transcription factor from e. coli in complex with fadb operator
Identifiers
SymbolFadR_C
PfamPF07840
Pfam clanCL0388
InterProIPR008920
SCOP21h9g / SCOPe / SUPFAM
Available protein structures:
Pfam  structures / ECOD  
PDBRCSB PDB; PDBe; PDBj
PDBsumstructure summary

Bacteria regulate membrane fluidity by manipulating the relative levels of saturated and unsaturated fatty acids within the phospholipids of their membrane bilayers. In Escherichia coli, the transcription factor, FadR, functions as a switch that co-ordinately regulates the machinery required for fatty acid beta-oxidation and the expression of a key enzyme in fatty acid biosynthesis. This single [repressor controls the transcription of the whole fad regulon.[1] Binding of fadR is specifically inhibited by long chain fatty acyl-CoA compounds.

The crystal structure of FadR reveals a two domain dimeric molecule where the N-terminal winged-helix domain binds DNA, and the C-terminal domain binds acyl-CoA.[1] The binding of acyl-CoA to the C-terminal domain results in a conformational change that affects the DNA binding affinity of the N-terminal domain.[2]

FadR is a member of the GntR family of bacterial transcription regulators. The DNA-binding domain is well conserved for this family, whereas the C-terminal effector-binding domain is more variable, and is consequently used to define the GntR subfamilies.[3] The FadR group is the largest subgroup, and is characterised by an all-helical C-terminal domain composed of 6 to 7 alpha helices.[2]

References edit

  1. ^ a b Xu Y, Heath RJ, Li Z, Rock CO, White SW (May 2001). "The FadR.DNA complex. Transcriptional control of fatty acid metabolism in Escherichia coli". J. Biol. Chem. 276 (20): 17373–9. doi:10.1074/jbc.M100195200. PMID 11279025.
  2. ^ a b van Aalten DM, DiRusso CC, Knudsen J, Wierenga RK (October 2000). "Crystal structure of FadR, a fatty acid-responsive transcription factor with a novel acyl coenzyme A-binding fold". EMBO J. 19 (19): 5167–77. doi:10.1093/emboj/19.19.5167. PMC 302096. PMID 11013219.
  3. ^ Rigali S, Derouaux A, Giannotta F, Dusart J (April 2002). "Subdivision of the helix-turn-helix GntR family of bacterial regulators in the FadR, HutC, MocR, and YtrA subfamilies" (PDF). J. Biol. Chem. 277 (15): 12507–15. doi:10.1074/jbc.M110968200. PMID 11756427.