5BN5: Structural Basis For A Unique Atp Synthase Core Complex From Nanoarcheaum Equitans

ATP synthesis is a critical and universal life process carried out by ATP synthases. Whereas eukaryotic and prokaryotic ATP synthases are well characterized, archaeal ATP synthases are relatively poorly understood. The hyperthermophilic archaeal parasite, Nanoarcheaum equitans, lacks several subunits of the ATP synthase and is suspected to be energetically dependent on its host, Ignicoccus hospitalis. This suggests that this ATP synthase might be a rudimentary machine. Here, we report the crystal structures and biophysical studies of the regulatory subunit, NeqB, the apo-NeqAB, and NeqAB in complex with nucleotides, ADP, and adenylyl-imidodiphosphate (non-hydrolysable analog of ATP). NeqB is approximately 20 amino acids shorter at its C terminus than its homologs, but this does not impede its binding with NeqA to form the complex. The heterodimeric NeqAB complex assumes a closed, rigid conformation irrespective of nucleotide binding; this differs from its homologs, which require conformational changes for catalytic activity. Thus, although N. equitans possesses an ATP synthase core A3B3 hexameric complex, it might not function as a bona fide ATP synthase.
PDB ID: 5BN5Download
MMDB ID: 132672
PDB Deposition Date: 2015/5/25
Updated in MMDB: 2015/11
Experimental Method:
x-ray diffraction
Resolution: 3  Å
Similar Structures:
Biological Unit for 5BN5: dimeric; determined by author
Molecular Components in 5BN5
Label Count Molecule
Proteins (2 molecules)
V-type ATP Synthase Alpha Chain
Molecule annotation
Molecule annotation
Chemical (1 molecule)
* Click molecule labels to explore molecular sequence information.

Citing MMDB