1O7L

Molybdate-activated form of ModE from Escherichia coli

Summary for 1O7L

• Entry DOI: 10.2210/pdb1o7l/pdb
• Related: 1B9M 1B9N 1H9R 1H9S
• Descriptor: TRANSCRIPTIONAL REGULATOR MODE, MOLYBDATE ION, CHLORIDE ION, ... (5 entities in total)
• Functional Keywords: transcription regulation, dna binding, molybdate, mop, winged helix-turn-helix, transcriptional regulator, activator
• Biological source: ESCHERICHIA COLI
• Cellular location: Cytoplasm: P46930
• Total number of polymer chains: 4
• Total formula weight: 114107.80

Authors

Schuttelkopf, A.W.,Hunter, W.N. (deposition date: 2002-11-08, release date: 2003-02-20, Last modification date: 2023-12-13)

Primary citation

Schuttelkopf, A.W.,Boxer, D.H.,Hunter, W.N.
Crystal Structure of Activated Mode Reveals Conformational Changes Involving Both Oxyanion and DNA-Binding Domains
J.Mol.Biol., 326:761-, 2003

PubMed Abstract: 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 2.75A from a merohedrally twinned crystal (twin fraction approximately 0.30) with space group P4(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.

PubMed: 12581638
DOI: 10.1016/S0022-2836(02)01358-X

Experimental method

X-RAY DIFFRACTION (2.75 Å)