1RFY

Crystal Structure of Quorum-Sensing Antiactivator TraM


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.6 Å
  • R-Value Free: 0.222 
  • R-Value Work: 0.202 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

Quorum-sensing antiactivator TraM forms a dimer that dissociates to inhibit TraR

Chen, G.Malenkos, J.W.Cha, M.R.Fuqua, C.Chen, L.

(2004) Mol.Microbiol. 52: 1641-1651

  • DOI: 10.1111/j.1365-2958.2004.04110.x

  • PubMed Abstract: 
  • The quorum-sensing transcriptional activator TraR of Agrobacterium tumefaciens, which controls the replication and conjugal transfer of the tumour-inducing (Ti) virulence plasmid, is inhibited by the TraM antiactivator. The crystal structure of TraM ...

    The quorum-sensing transcriptional activator TraR of Agrobacterium tumefaciens, which controls the replication and conjugal transfer of the tumour-inducing (Ti) virulence plasmid, is inhibited by the TraM antiactivator. The crystal structure of TraM reveals this protein to form a homodimer in which the monomer primarily consists of two long coiled alpha-helices, and one of the helices from each monomer also bundles to form the dimeric interface. The importance of dimerization is addressed by mutational studies in which disruption of the hydrophobic dimer interface leads to aggregation of TraM. Biochemical studies confirm that TraM exists as a homodimer in solution in equilibrium with the monomeric form, and also establish that the TraM-TraR complex is a heterodimer. Thus, the TraM homodimer undergoes dissociation in forming the antiactivation complex. Combined with the structure of TraR (Zhang et al., 2002, Nature 417: 971-974; Vannini et al., 2002, EMBO J 21: 4393-4401), our structural analysis suggests overlapping interactive surfaces in homodimeric TraM with those in the TraM-TraR complex and a mechanism for TraM inhibition on TraR.


    Organizational Affiliation

    Department of Biology, Indiana University, 915 E. 3rd St., Bloomington, IN 47405, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Transcriptional repressor traM
A, B
102Rhizobium radiobacterMutation(s): 0 
Gene Names: traM
Find proteins for Q57471 (Rhizobium radiobacter)
Go to UniProtKB:  Q57471
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.6 Å
  • R-Value Free: 0.222 
  • R-Value Work: 0.202 
  • Space Group: C 2 2 2
Unit Cell:
Length (Å)Angle (°)
a = 78.230α = 90.00
b = 85.750β = 90.00
c = 67.020γ = 90.00
Software Package:
Software NamePurpose
SnBphasing
SCALEPACKdata scaling
CNSrefinement
SOLVEphasing
DENZOdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2004-11-23
    Type: Initial release
  • Version 1.1: 2008-04-29
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Derived calculations, Version format compliance
  • Version 1.3: 2017-10-11
    Type: Refinement description