1NG1

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

Summary for 1NG1

• Entry DOI: 10.2210/pdb1ng1/pdb
• Descriptor: SIGNAL SEQUENCE RECOGNITION PROTEIN FFH, CADMIUM ION, MAGNESIUM ION, ... (7 entities in total)
• Functional Keywords: ffh, srp, gtpase, signal recognition particle, gdp, mg, signal recognition
• Biological source: Thermus aquaticus
• Total number of polymer chains: 1
• Total formula weight: 33555.83

Authors

Freymann, D.M.,Stroud, R.M.,Walter, P. (deposition date: 1998-04-30, release date: 1999-07-30, Last modification date: 2024-05-22)

Primary citation

Freymann, D.M.,Keenan, R.J.,Stroud, R.M.,Walter, P.
Functional changes in the structure of the SRP GTPase on binding GDP and Mg2+GDP.
Nat.Struct.Biol., 6:793-801, 1999

PubMed 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.

PubMed: 10426959
DOI: 10.1038/11572

Experimental method

X-RAY DIFFRACTION (2.03 Å)