| Structural highlights
3oqm 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.
| | Ligands: | |
| NonStd Res: | |
| Related: | 3oqn, 3oqo |
| Gene: | alsA, amyR, BSU29740, ccpA, graR (Bacillus subtilis), BSU13900, hpr, ptsH (Bacillus subtilis) |
| Resources: | FirstGlance, OCA, RCSB, PDBsum |
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] [PTHP_BACSU] General (non sugar-specific) component of the phosphoenolpyruvate-dependent sugar phosphotransferase system (sugar PTS). This major carbohydrate active-transport system catalyzes the phosphorylation of incoming sugar substrates concomitantly with their translocation across the cell membrane. The phosphoryl group from phosphoenolpyruvate (PEP) is transferred to the phosphoryl carrier protein HPr by enzyme I. Phospho-HPr then transfers it to the permease (enzymes II/III).[6] [7] P-Ser-HPr interacts with the catabolite control protein A (CcpA), forming a complex that binds to DNA at the catabolite response elements cre, operator sites preceding a large number of catabolite-regulated genes. Thus, P-Ser-HPr is a corepressor in carbon catabolite repression (CCR), a mechanism that allows bacteria to coordinate and optimize the utilization of available carbon sources. P-Ser-HPr also plays a role in inducer exclusion, in which it probably interacts with several non-PTS permeases and inhibits their transport activity.[8] [9]
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[10]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ 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
- ↑ 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
- ↑ 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
- ↑ 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
- ↑ 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
- ↑ Deutscher J, Reizer J, Fischer C, Galinier A, Saier MH Jr, Steinmetz M. Loss of protein kinase-catalyzed phosphorylation of HPr, a phosphocarrier protein of the phosphotransferase system, by mutation of the ptsH gene confers catabolite repression resistance to several catabolic genes of Bacillus subtilis. J Bacteriol. 1994 Jun;176(11):3336-44. PMID:8195089
- ↑ Fujita Y, Miwa Y, Galinier A, Deutscher J. Specific recognition of the Bacillus subtilis gnt cis-acting catabolite-responsive element by a protein complex formed between CcpA and seryl-phosphorylated HPr. Mol Microbiol. 1995 Sep;17(5):953-60. PMID:8596444
- ↑ Deutscher J, Reizer J, Fischer C, Galinier A, Saier MH Jr, Steinmetz M. Loss of protein kinase-catalyzed phosphorylation of HPr, a phosphocarrier protein of the phosphotransferase system, by mutation of the ptsH gene confers catabolite repression resistance to several catabolic genes of Bacillus subtilis. J Bacteriol. 1994 Jun;176(11):3336-44. PMID:8195089
- ↑ Fujita Y, Miwa Y, Galinier A, Deutscher J. Specific recognition of the Bacillus subtilis gnt cis-acting catabolite-responsive element by a protein complex formed between CcpA and seryl-phosphorylated HPr. Mol Microbiol. 1995 Sep;17(5):953-60. PMID:8596444
- ↑ 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
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