Crystal Structure of Activated ModE Reveals Conformational Changes Involving Both Oxyanion and DNA-binding Domains
| Autor: | William N. Hunter, Alexander W. Schüttelkopf, David H. Boxer |
|---|---|
| Rok vydání: | 2003 |
| Předmět: |
Anions
Models Molecular Conformational change Protein Conformation Stereochemistry Dimer Molecular Sequence Data Oxyanion Crystal structure Biology Crystallography X-Ray chemistry.chemical_compound Bacterial Proteins Structural Biology Amino Acid Sequence Molecular Biology Escherichia coli Proteins DNA DNA-binding domain Oxygen Crystallography chemistry Docking (molecular) Crystal twinning Protein Binding Transcription Factors |
| Zdroj: | Journal of Molecular Biology. 326:761-767 |
| ISSN: | 0022-2836 |
| DOI: | 10.1016/s0022-2836(02)01358-x |
| Popis: | ModE is a bacterial transcriptional regulator that orchestrates many aspects of molybdenum metabolism by binding to specific DNA sequences in a molybdate-dependent fashion. We present the crystal structure of Escherichia coli ModE in complex with molybdate, which was determined at 2.75 A from a merohedrally twinned crystal (twin fraction≈0.30) with space group P 4 3 . We now have structures of ModE in both its “switched on” (ligand-bound) and “switched off” (apo) states. Comparison with the apo structure shows that ligand binding leads to extensive conformational changes not only in the molybdate-binding domain, but also in the DNA-binding domain. The most obvious difference is the loss of the pronounced asymmetry between the two chains of the ModE dimer, which had been a characteristic property of the apo structure. Another major change concerns the relative orientation of the two DNA-interacting winged helix-turn-helix motifs. Manual docking of an idealized DNA structure suggests that this conformational change should improve DNA binding of the activated molybdate-bound ModE. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect