ATP synthase subunit alpha, N-terminal domain-like superfamily (IPR023366)
Short name: ATP_synth_asu-like_sf
- Lumazine-binding protein (IPR001783)
- ATP synthase, F1 complex, alpha subunit (IPR005294)
- ATPase, V1 complex, subunit A (IPR005725)
- ATP synthase alpha chain, archaea (IPR005726)
- Alternate ATP synthase, F1 complex, subunit alpha (IPR017710)
- V-type ATP synthase catalytic alpha chain (IPR022878)
- Lumazine-binding domain (IPR026017)
In F-ATPases, there are three copies each of the alpha and beta subunits that form the catalytic core of the F1 complex, while the remaining F1 subunits (gamma, delta, epsilon) form part of the stalks. There is a substrate-binding site on each of the alpha and beta subunits, those on the beta subunits being catalytic, while those on the alpha subunits are regulatory. The alpha and beta subunits form a cylinder that is attached to the central stalk. The alpha/beta subunits undergo a sequence of conformational changes leading to the formation of ATP from ADP, which are induced by the rotation of the gamma subunit, itself is driven by the movement of protons through the F0 complex C subunit [PMID: 12745923]. In V- and A-ATPases, the alpha/A and beta/B subunits of the V1 or A1 complex are homologous to the alpha and beta subunits in the F1 complex of F-ATPases, except that the alpha subunit is catalytic and the beta subunit is regulatory.
The alpha/A and beta/B subunits can each be divided into three regions, or domains, centred around the ATP-binding pocket, and based on structure and function, where the central region is the nucleotide-binding domain (IPR000194) [PMID: 12885621].
This superfamily represents a closed beta-barrel domain with Greek-key topology. It is found at the N terminus of the alpha/A subunits. This beta barrel closely resembles folds found in riboflavin synthase [PMID: 11377200].
- G3DSA:126.96.36.199 (G3DSA:188.8.131.52)