1FFH

N AND GTPASE DOMAINS OF THE SIGNAL SEQUENCE RECOGNITION PROTEIN FFH FROM THERMUS AQUATICUS


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.05 Å
  • R-Value Free: 0.248 
  • R-Value Work: 0.186 
  • R-Value Observed: 0.186 

wwPDB Validation   3D Report Full Report


This is version 1.3 of the entry. See complete history


Literature

Structure of the conserved GTPase domain of the signal recognition particle.

Freymann, D.M.Keenan, R.J.Stroud, R.M.Walter, P.

(1997) Nature 385: 361-364

  • DOI: https://doi.org/10.1038/385361a0
  • Primary Citation of Related Structures:  
    1FFH

  • PubMed Abstract: 

    The signal-recognition particle (SRP) and its receptor (SR) function in the co-translational targeting of nascent protein-ribosome complexes to the membrane translocation apparatus. The SRP protein subunit (termed Ffh in bacteria) that recognizes the signal sequence of nascent polypeptides is a GTPase, as is the SR-alpha subunit (termed FtsY). Ffh and FtsY interact directly, each stimulating the GTP hydrolysis activity of the other. The sequence of Ffh suggests three domains: an amino-terminal N domain of unknown function, a central GTPase G domain, and a methionine-rich M domain that binds both SRP RNA and signal peptides. Sequence conservation suggests that structurally similar N and G domains are present in FtsY. Here we report the structure of the nucleotide-free form of the NG fragment of Ffh. Consistent with a role for apo Ffh in protein targeting, the side chains of the empty active-site pocket form a tight network of interactions which may stabilize the nucleotide-free protein. The structural relationship between the two domains suggests that the N domain senses or controls the nucleotide occupancy of the GTPase domain. A structural subdomain unique to these evolutionarily conserved GTPases constitutes them as a distinct subfamily in the GTPase superfamily.


  • Organizational Affiliation

    Department of Biochemistry and Biophysics, School of Medicine, University of California, San Francisco 94143-0448, USA. freymann@msg.ucsf.edu


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
FFH294Thermus aquaticusMutation(s): 0 
Gene Names: FFH
EC: 3.6.5.4
UniProt
Find proteins for O07347 (Thermus aquaticus)
Explore O07347 
Go to UniProtKB:  O07347
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupO07347
Sequence Annotations
Expand
  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
MG
Query on MG

Download Ideal Coordinates CCD File 
B [auth A]MAGNESIUM ION
Mg
JLVVSXFLKOJNIY-UHFFFAOYSA-N
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.05 Å
  • R-Value Free: 0.248 
  • R-Value Work: 0.186 
  • R-Value Observed: 0.186 
  • Space Group: C 1 2 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 99.9α = 90
b = 53.91β = 119.77
c = 57.36γ = 90
Software Package:
Software NamePurpose
X-PLORmodel building
X-PLORrefinement
DENZOdata reduction
SCALEPACKdata scaling
X-PLORphasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 1997-12-31
    Type: Initial release
  • Version 1.1: 2008-03-24
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 1.3: 2024-02-07
    Changes: Data collection, Database references, Derived calculations, Other