1OKK: Homo-Heterodimeric Complex Of The Srp Gtpases

Citation:
Abstract
Two structurally homologous guanosine triphosphatase (GTPase) domains interact directly during signal recognition particle (SRP)-mediated cotranslational targeting of proteins to the membrane. The 2.05 angstrom structure of a complex of the NG GTPase domains of Ffh and FtsY reveals a remarkably symmetric heterodimer sequestering a composite active site that contains two bound nucleotides. The structure explains the coordinate activation of the two GTPases. Conformational changes coupled to formation of their extensive interface may function allosterically to signal formation of the targeting complex to the signal-sequence binding site and the translocon. We propose that the complex represents a molecular "latch" and that its disengagement is regulated by completion of assembly of the GTPase active site.
PDB ID: 1OKKDownload
MMDB ID: 26049
PDB Deposition Date: 2003/7/26
Updated in MMDB: 2012/10
Experimental Method:
x-ray diffraction
Resolution: 2.05  Å
Source Organism:
Similar Structures:
Biological Unit for 1OKK: dimeric; determined by author and by software (PQS)
Molecular Components in 1OKK
Label Count Molecule
Proteins (2 molecules)
1
Signal Recognition Particle Protein
Molecule annotation
1
Cell Division Protein Ftsy
Molecule annotation
Chemicals (21 molecules)
1
2
2
2
3
2
4
11
5
4
* Click molecule labels to explore molecular sequence information.

Citing MMDB
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