1SXI
Structure of apo transcription regulator B. megaterium
Summary for 1SXI
| Entry DOI | 10.2210/pdb1sxi/pdb |
| Related | 1SXG 1SXH |
| Descriptor | Glucose-resistance amylase regulator, MAGNESIUM ION (3 entities in total) |
| Functional Keywords | allosterism; phosphoprotein; transcription regulation; gram positive bacteria; ccr, transcription |
| Biological source | Bacillus megaterium |
| Total number of polymer chains | 12 |
| Total formula weight | 376455.86 |
| Authors | Schumacher, M.A.,Allen, G.S.,Diel, M.,Seidel, G.,Hillen, W.,Brennan, R.G. (deposition date: 2004-03-30, release date: 2004-10-19, Last modification date: 2024-11-13) |
| Primary citation | Schumacher, M.A.,Allen, G.S.,Diel, M.,Seidel, G.,Hillen, W.,Brennan, R.G. Structural studies on the apo transcription factor form B. megaterium Cell(Cambridge,Mass.), 118:731-741, 2004 Cited by PubMed Abstract: Carbon catabolite repression (CCR) is one of the most fundamental environmental-sensing mechanisms in bacteria and imparts competitive advantage by establishing priorities in carbon metabolism. In gram-positive bacteria, the master transcription regulator of CCR is CcpA. CcpA is a LacI-GalR family member that employs, as an allosteric corepressor, the phosphoprotein HPr-Ser46-P, which is formed in glucose-replete conditions. Here we report structures of the Bacillus megaterium apoCcpA and a CcpA-(HPr-Ser46-P)-DNA complex. These structures reveal that HPr-Ser46-P mediates a novel two-component allosteric DNA binding activation mechanism that involves both rotation of the CcpA subdomains and relocation of pivot-point residue Thr61, which leads to juxtaposition of the DNA binding regions permitting "hinge" helix formation in the presence of cognate DNA. The structure of the CcpA-(HPr-Ser46-P)-cre complex also reveals the elegant mechanism by which CcpA family-specific interactions with HPr-Ser46-P residues Ser46-P and His15 partition the high-energy CCR and low-energy PTS pathways, the latter requiring HPr-His15-P. PubMed: 15369672DOI: 10.1016/j.cell.2004.08.027 PDB entries with the same primary citation |
| Experimental method | X-RAY DIFFRACTION (3 Å) |
Structure validation
Download full validation report
