Rotation of the Proteolipid Ring in the V-ATPase

• Published in: The Journal of biological chemistry 2003-07, Vol.278 (27), p.24255-24258
• Main Authors: Yokoyama, Ken, Nakano, Masahiro, Imamura, Hiromi, Yoshida, Masasuke, Tamakoshi, Masatada
• Format: Article
• Language: English
• Subjects: Models, Molecular; Proteolipids - chemistry; Rotation; Structure-Activity Relationship; Thermus thermophilus - chemistry; Thermus thermophilus - enzymology; Vacuolar Proton-Translocating ATPases - chemistry
• ISSN: 0021-9258; 1083-351X
• DOI: 10.1074/jbc.M303104200

V 0 V 1 -ATPase is a proton-translocating ATPase responsible for acidification of eukaryotic intracellular compartments and for ATP synthesis in archaea and some eubacteria. We demonstrated recently the rotation of the central stalk subunits in V 1 , a catalytic sector of V 0 V 1 -ATPase (Imamura, H., Nakano, M., Noji, H., Muneyuki, E., Ohkuma, S., Yoshida, M., and Yokoyama, K. (2003) Proc. Natl. Acad. Sci. U. S. A. 100, 2312–2315), but the rotation of the proteolipid ring, a predicted counterpart rotor in the membrane V 0 sector, has remained to be proven. V 0 V 1 -ATPase that retained sensitivity to N ′, N ′-dicyclohexylcarbodiimide was isolated from Thermus thermophilus , immobilized onto a glass surface through the N termini of the A subunits of V 1 , and decorated with a bead attached to a proteolipid subunit of V 0 . Rotation of beads was observed in the presence of ATP, and direction of rotation was always counterclockwise viewed from the membrane side. The rotation proceeded at ∼3.0 rev/s in average at 4 m m ATP and was abolished by N ′, N ′-dicyclohexylcarbodiimide treatment. Thus, the rotation of the central stalk in V 1 accompanies rotation of a proteolipid ring of V 0 in the functioning V 0 V 1 -ATPase.