ATP synthesis of Enterococcus hirae V-ATPase driven by sodium motive force.

ABSTRACT: V-ATPases generally function as ion pumps driven by ATP hydrolysis in the cell, but their capability of ATP synthesis remains largely unexplored. Here we show ATP synthesis of Na⁺-transporting Enterococcus hirae V-ATPase (EhV_oV₁) driven by the electrochemical potential gradient of Na⁺ across the membrane (sodium motive force, smf). We reconstituted EhV_oV₁ into liposome and performed a luciferin/luciferase-based assay to analyze ATP synthesis quantitatively. Our result demonstrates that EhV_oV₁ synthesizes ATP with a rate of 4.7 s^-1 under high smf (269.3 mV). The Michaelis constants for ADP (21 μM) and inorganic phosphate (2.1 mM) in ATP synthesis reaction were comparable to those for ATP synth

SUBMITTER: Otomo A 

PROVIDER: S-EPMC12018189 | biostudies-literature | 2025 Mar

REPOSITORIES: biostudies-literature