3NG1 : N AND GTPASE DOMAINS OF THE SIGNAL SEQUENCE RECOGNITION PROTEIN FFH FROM THERMUS AQUATICUS

  • Douglas M. Freymann (Northwestern University) (Contributor)
  • Robert M. Stroud (Contributor)
  • Peter Walter (Contributor)

Dataset

Description

Experimental Technique/Method:X-RAY DIFFRACTION
Resolution:2.3
Classification:SIGNAL RECOGNITION
Release Date:1999-07-30
Deposition Date:1998-09-13
Revision Date:2008-03-25#2011-07-13
Molecular Weight:65715.61
Macromolecule Type:Protein
Residue Count:588
Atom Site Count:4566
DOI:10.2210/pdb3ng1/pdb

Abstract:
Ffh is a component of a bacterial ribonucleoprotein complex homologous to the signal recognition particle (SRP) of eukaryotes. It comprises three domains that mediate both binding to the hydrophobic signal sequence of the nascent polypeptide and the GTP-dependent interaction of Ffh with a structurally homologous GTPase of the SRP receptor. The X-ray structures of the two-domain 'NG' GTPase of Ffh in complex with Mg2+GDP and GDP have been determined at 2.0 A resolution. The structures explain the low nucleotide affinity of Ffh and locate two regions of structural mobility at opposite sides of the nucleotide-binding site. One of these regions includes highly conserved sequence motifs that presumably contribute to the structural trigger signaling the GTP-bound state. The other includes the highly conserved interface between the N and G domains, and supports the hypothesis that the N domain regulates or signals the nucleotide occupancy of the G domain.
Date made available1999
PublisherRCSB-PDB

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