7x7h

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Crystal structure of Fructose regulator/Histidine phosphocarrier protein complex from Vibrio choleraeCrystal structure of Fructose regulator/Histidine phosphocarrier protein complex from Vibrio cholerae

Structural highlights

7x7h is a 4 chain structure with sequence from Vibrio cholerae. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:X-ray diffraction, Resolution 2Å
Ligands:
Resources:FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

FRUR_VIBCH Regulates the expression of the fruBKA (fru) operon, which encodes proteins involved in the import and metabolism of fructose (PubMed:33476373, PubMed:33649152). In the absence of fructose 1-phosphate (F1P), binds to the promoter region of fruB, interferes with the binding of the RNA polymerase (RNAP) to the promoter and represses the expression of the operon (PubMed:33476373, PubMed:33649152). In the presence of F1P, activates the transcription of the fru operon by facilitating the binding of RNAP to the promoter (PubMed:33476373). Essential for the expression of the fru operon and thus for growth on fructose (PubMed:33476373).[1] [2]

Publication Abstract from PubMed

Phosphorylation state-dependent interactions of the phosphoenolpyruvate (PEP):carbohydrate phosphotransferase system (PTS) components with transcription factors play a key role in carbon catabolite repression (CCR) by glucose in bacteria. Glucose inhibits the PTS-dependent transport of fructose and is preferred over fructose in Vibrio cholerae, but the mechanism is unknown. We have recently shown that, contrary to Escherichia coli, the fructose-dependent transcriptional regulator FruR acts as an activator of the fru operon in V. cholerae and binding of the FruR-fructose 1-phosphate (F1P) complex to an operator facilitates RNA polymerase (RNAP) binding to the fru promoter. Here we show that, in the presence of glucose, dephosphorylated HPr, a general PTS component, binds to FruR. Whereas HPr does not affect DNA-binding affinity of FruR, regardless of the presence of F1P, it prevents the FruR-F1P complex from facilitating the binding of RNAP to the fru promoter. Structural and biochemical analyses of the FruR-HPr complex identify key residues responsible for the V. cholerae-specific FruR-HPr interaction not observed in E. coli. Finally, we reveal how the dephosphorylated HPr interacts with FruR in V. cholerae, whereas the phosphorylated HPr binds to CcpA, which is a global regulator of CCR in Bacillus subtilis and shows structural similarity to FruR.

HPr prevents FruR-mediated facilitation of RNA polymerase binding to the fru promoter in Vibrio cholerae.,Yoon CK, Lee SH, Zhang J, Lee HY, Kim MK, Seok YJ Nucleic Acids Res. 2023 Jun 23;51(11):5432-5448. doi: 10.1093/nar/gkad220. PMID:36987873[3]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

See Also

References

  1. Yoon CK, Kang D, Kim MK, Seok YJ. Vibrio cholerae FruR facilitates binding of RNA polymerase to the fru promoter in the presence of fructose 1-phosphate. Nucleic Acids Res. 2021 Feb 22;49(3):1397-1410. PMID:33476373 doi:10.1093/nar/gkab013
  2. Beck C, Perry S, Stoebel DM, Liu JM. Cra and cAMP Receptor Protein Have Opposing Roles in the Regulation of fruB in Vibrio cholerae. J Bacteriol. 2021 Apr 21;203(10):e00044-21. PMID:33649152 doi:10.1128/JB.00044-21
  3. Yoon CK, Lee SH, Zhang J, Lee HY, Kim MK, Seok YJ. HPr prevents FruR-mediated facilitation of RNA polymerase binding to the fru promoter in Vibrio cholerae. Nucleic Acids Res. 2023 Jun 23;51(11):5432-5448. PMID:36987873 doi:10.1093/nar/gkad220

7x7h, resolution 2.00Å

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