3OQM

structure of ccpa-hpr-ser46p-ackA2 complex

Summary for 3OQM

• Entry DOI: 10.2210/pdb3oqm/pdb
• Related: 3OQN 3OQO
• Descriptor: Catabolite control protein A, Phosphocarrier protein HPr, 5'-D(*TP*TP*GP*TP*AP*AP*GP*CP*GP*TP*TP*AP*TP*CP*AP*A)-3', ... (6 entities in total)
• Functional Keywords: pbp fold for ccpa, transcription, hpr-ser46-p and cre dna, nucleoid, transcription-transferase-dna complex, transcription/transferase/dna
• Biological source: Bacillus subtilis; More
• Cellular location: Cytoplasm: P08877
• Total number of polymer chains: 6
• Total formula weight: 103920.00

Authors

Schumacher, M.A.,Sprehe, M.,Bartholomae, M.,Hillen, W.,Brennan, R.G. (deposition date: 2010-09-03, release date: 2010-12-08, Last modification date: 2023-09-06)

Primary citation

Schumacher, M.A.,Sprehe, M.,Bartholomae, M.,Hillen, W.,Brennan, R.G.
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., 39:2931-2942, 2011

PubMed Abstract: 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° to 56°. 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.

PubMed: 21106498
DOI: 10.1093/nar/gkq1177

Experimental method

X-RAY DIFFRACTION (2.96 Å)