ATP synthase delta/OSCP subunit

ATP synthase delta subunit is a subunit of bacterial and chloroplast F-ATPase/synthase. It is known as OSCP (oligomycin sensitivity conferral protein) in mitochondrial ATPase (note that in mitochondria there is a different delta subunit, ATP synthase delta/epsilon subunit).

ATP synthase delta (OSCP) subunit
Structure of the N-terminal domain of the delta subunit of the E. coli ATPsynthase.[1]
Identifiers
Symbol	OSCP
Pfam	PF00213
InterPro	IPR000711
PROSITE	PDOC00327
SCOP2	1abv / SCOPe / SUPFAM
TCDB	3.A.2
Available protein structures: Pfam   structures / ECOD   PDB RCSB PDB; PDBe; PDBj PDBsum structure summary PDB 2a7uB:7-135 1abv :7-106 2bo5A:37-143

The OSCP/delta subunit appears to be part of the peripheral stalk that holds the F₁ complex α3β3 catalytic core stationary against the torque of the rotating central stalk, and links subunit A of the F_O complex with the F₁ complex. In mitochondria, the peripheral stalk consists of OSCP, as well as F_O components F6, B and D. In bacteria and chloroplasts the peripheral stalks have different subunit compositions: delta and two copies of F_O component B (bacteria), or delta and F_O components B and B' (chloroplasts).^[2]

F-ATPases lacking this subunit generally transport sodium instead of protons. They are proposed to be called N-ATPases, since they seem to form a distinct group that is further apart from usual F-ATPases than A-ATPases are from V-ATPases.^[3]

Human delta subunit of ATP synthase is coded by gene ATP5O.

References

1. Wilkens S, Dunn SD, Chandler J, Dahlquist FW, Capaldi RA (March 1997). "Solution structure of the N-terminal domain of the delta subunit of the E. coli ATPsynthase". Nat. Struct. Biol. 4 (3): 198–201. doi:10.1038/nsb0397-198. PMID 9164460. S2CID 11261505.
2. Walker JE, Runswick MJ, Neuhaus D, Montgomery MG, Carbajo RJ, Kellas FA (2005). "Structure of the F1-binding domain of the stator of bovine F1Fo-ATPaseand how it binds an alpha-subunit". J. Mol. Biol. 351 (4): 824–838. doi:10.1016/j.jmb.2005.06.012. PMID 16045926.
3. Dibrova, DV; Galperin, MY; Mulkidjanian, AY (15 June 2010). "Characterization of the N-ATPase, a distinct, laterally transferred Na+-translocating form of the bacterial F-type membrane ATPase". Bioinformatics. 26 (12): 1473–6. doi:10.1093/bioinformatics/btq234. PMC 2881411. PMID 20472544.

Further reading

Wilkens, S.; Rodgers, A.; Ogilvie, I.; Capaldi, R. A. (1997). "Structure and arrangement of the delta subunit in the E. Coli ATP synthase (ECF1F0)". Biophysical Chemistry. 68 (1–3): 95–102. doi:10.1016/s0301-4622(97)00018-5. PMID 9468613.

This article incorporates text from the public domain Pfam and InterPro: IPR000711