1I1S

SOLUTION STRUCTURE OF THE TRANSCRIPTIONAL ACTIVATION DOMAIN OF THE BACTERIOPHAGE T4 PROTEIN MOTA


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 200 
  • Conformers Submitted: 20 
  • Selection Criteria: structures with the lowest energy 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Solution structure of the transcriptional activation domain of the bacteriophage T4 protein, MotA.

Li, N.Zhang, W.White, S.W.Kriwacki, R.W.

(2001) Biochemistry 40: 4293-4302


  • PubMed Abstract: 
  • Bacteriophage T4 encodes a transcription factor, MotA, that binds to the -30 region of middle-mode promoters and activates transcription by host RNA polymerase. The crystal structure of the N-terminal domain of MotA (MotNF) revealed a six-helix domai ...

    Bacteriophage T4 encodes a transcription factor, MotA, that binds to the -30 region of middle-mode promoters and activates transcription by host RNA polymerase. The crystal structure of the N-terminal domain of MotA (MotNF) revealed a six-helix domain in which the two C-terminal alpha-helices mediate the formation of a dimer via a coiled-coil motif and hydrophobic interactions. This structure suggested that full-length MotA binds DNA as a dimer, but subsequent biochemical results have shown that a monomeric form of MotA binds DNA. In this study, gel filtration chromatography, dynamic light scattering, and NMR-based diffusion measurements show conclusively that MotNF is a monomer, and not a dimer, in solution. In addition, we have determined the monomeric solution structure of MotNF using NMR spectroscopy, and have compared this with the dimer structure observed in crystals. The core of the protein assumes the same helical conformation in solution and in crystals, but important differences are observed at the extreme C-terminus. In solution, helix alpha5 is followed by five disordered residues that probably link the N-terminal and C-terminal domains of MotA. In crystals, helix alpha5 forms the dimer interface and is followed by a short sixth helix that further stabilizes the dimer configuration. The solution structure of MotNF supports the conclusion that MotA functions as a monomer, and suggests that the existence of the sixth helix in crystals is a consequence of crystal packing. Our work highlights the importance of investigating protein structures in both crystals and solution to fully understand biomolecular structure and to accurately deduce relationships between structure and function.


    Organizational Affiliation

    Department of Structural Biology, St. Jude Children's Research Hospital, 332 North Lauderdale Street, Memphis, Tennessee 38105, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
MOTA
A
96Enterobacteria phage T4Mutation(s): 0 
Gene Names: motA
Find proteins for P22915 (Enterobacteria phage T4)
Go to UniProtKB:  P22915
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 200 
  • Conformers Submitted: 20 
  • Selection Criteria: structures with the lowest energy 
  • Olderado: 1I1S Olderado

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2001-02-14
    Type: Initial release
  • Version 1.1: 2008-04-27
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance