Structure of ccpa-hpr-ser46-p-gntr-down creStructure of ccpa-hpr-ser46-p-gntr-down cre

Structural highlights

3oqn is a 6 chain structure with sequence from Bacillus subtilis. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:X-ray diffraction, Resolution 3.3Å
Ligands:
Resources:FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

CCPA_BACSU Global transcriptional regulator of carbon catabolite repression (CCR) and carbon catabolite activation (CCA), which ensures optimal energy usage under diverse conditions. Interacts with either P-Ser-HPr or P-Ser-Crh, leading to the formation of a complex that binds to DNA at the catabolite-response elements (cre). Binding to DNA allows activation or repression of many different genes and operons.[1] [2] [3] [4] [5]

Publication Abstract from PubMed

In Gram-positive bacteria, carbon catabolite protein A (CcpA) is the master regulator of carbon catabolite control, which ensures optimal energy usage under diverse conditions. Unlike other LacI-GalR proteins, CcpA is activated for DNA binding by first forming a complex with the phosphoprotein HPr-Ser46-P. Bacillus subtilis CcpA functions as both a transcription repressor and activator and binds to more than 50 operators called catabolite response elements (cres). These sites are highly degenerate with the consensus, WTGNNARCGNWWWCAW. How CcpA-(HPr-Ser46-P) binds such diverse sequences is unclear. To gain insight into this question, we solved the structures of the CcpA-(HPr-Ser46-P) complex bound to three different operators, the synthetic (syn) cre, ackA2 cre and gntR-down cre. Strikingly, the structures show that the CcpA-bound operators display different bend angles, ranging from 31 degrees to 56 degrees . These differences are accommodated by a flexible linkage between the CcpA helix-turn-helix-loop-helix motif and hinge helices, which allows independent docking of these DNA-binding modules. This flexibility coupled with an abundance of non-polar residues capable of non-specific nucleobase interactions permits CcpA-(HPr-Ser46-P) to bind diverse operators. Indeed, biochemical data show that CcpA-(HPr-Ser46-P) binds the three cre sites with similar affinities. Thus, the data reveal properties that license this protein to function as a global transcription regulator.

Structures of carbon catabolite protein A-(HPr-Ser46-P) bound to diverse catabolite response element sites reveal the basis for high-affinity binding to degenerate DNA operators.,Schumacher MA, Sprehe M, Bartholomae M, Hillen W, Brennan RG Nucleic Acids Res. 2010 Nov 23. PMID:21106498[6]

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

See Also

References

  1. Henkin TM, Grundy FJ, Nicholson WL, Chambliss GH. Catabolite repression of alpha-amylase gene expression in Bacillus subtilis involves a trans-acting gene product homologous to the Escherichia coli lacl and galR repressors. Mol Microbiol. 1991 Mar;5(3):575-84. PMID:1904524
  2. Kim JH, Guvener ZT, Cho JY, Chung KC, Chambliss GH. Specificity of DNA binding activity of the Bacillus subtilis catabolite control protein CcpA. J Bacteriol. 1995 Sep;177(17):5129-34. PMID:7665492
  3. Tobisch S, Zuhlke D, Bernhardt J, Stulke J, Hecker M. Role of CcpA in regulation of the central pathways of carbon catabolism in Bacillus subtilis. J Bacteriol. 1999 Nov;181(22):6996-7004. PMID:10559165
  4. Ludwig H, Stulke J. The Bacillus subtilis catabolite control protein CcpA exerts all its regulatory functions by DNA-binding. FEMS Microbiol Lett. 2001 Sep 11;203(1):125-9. PMID:11557150
  5. Schumacher MA, Sprehe M, Bartholomae M, Hillen W, Brennan RG. Structures of carbon catabolite protein A-(HPr-Ser46-P) bound to diverse catabolite response element sites reveal the basis for high-affinity binding to degenerate DNA operators. Nucleic Acids Res. 2010 Nov 23. PMID:21106498 doi:10.1093/nar/gkq1177
  6. Schumacher MA, Sprehe M, Bartholomae M, Hillen W, Brennan RG. Structures of carbon catabolite protein A-(HPr-Ser46-P) bound to diverse catabolite response element sites reveal the basis for high-affinity binding to degenerate DNA operators. Nucleic Acids Res. 2010 Nov 23. PMID:21106498 doi:10.1093/nar/gkq1177

3oqn, resolution 3.30Å

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