3QYX

Crystal structure of Mycobacterium tuberculosis EspR in complex with a small DNA fragment

Summary for 3QYX

• Entry DOI: 10.2210/pdb3qyx/pdb
• Related: 3QF3 3QWG
• Descriptor: ESX-1 secretion-associated regulator EspR, 5'-D(*A*CP*GP*CP*CP*GP*AP*AP*TP*C)-3' (2 entities in total)
• Functional Keywords: n-terminal hth motif, c-terminal dimerization domain, dna-binding, transcription factor, dimer of dimers binding dna, transcription activator, transcription-dna complex, transcription/dna
• Biological source: Mycobacterium tuberculosis
• Cellular location: Secreted: P96228
• Total number of polymer chains: 5
• Total formula weight: 61980.38

Authors

Blasco, B.,Pojer, F.,Cole, S.T. (deposition date: 2011-03-04, release date: 2011-09-14, Last modification date: 2024-04-03)

Primary citation

Blasco, B.,Stenta, M.,Alonso-Sarduy, L.,Dietler, G.,Peraro, M.D.,Cole, S.T.,Pojer, F.
Atypical DNA recognition mechanism used by the EspR virulence regulator of Mycobacterium tuberculosis.
Mol.Microbiol., 82:251-264, 2011

PubMed Abstract: The human pathogen Mycobacterium tuberculosis requires the ESX-1 secretion system for full virulence. EspR plays a key role in ESX-1 regulation via direct binding and transcriptional activation of the espACD operon. Here, we describe the crystal structures of EspR, a C-terminally truncated form, EspRΔ10, as well as an EspR-DNA complex. EspR forms a dimer with each monomer containing an N-terminal helix-turn-helix DNA binding motif and an atypical C-terminal dimerization domain. Structural studies combined with footprinting experiments, atomic force microscopy and molecular dynamic simulations allow us to propose a model in which a dimer of EspR dimers is the minimal functional unit with two subunits binding two consecutive major grooves. The other two DNA binding domains are thus free to form higher-order oligomers and to bridge distant DNA sites in a cooperative way. These features are reminiscent of nucleoid-associated proteins and suggest a more general regulatory role for EspR than was previously suspected.

PubMed: 21883526
DOI: 10.1111/j.1365-2958.2011.07813.x

Experimental method

X-RAY DIFFRACTION (3.75 Å)