3.A.2.1.9
Sodium (Na⁺)-pumping F-type ATPase.  ATPase activity is stimulated by Na⁺ (Wiangnon et al. 2007), and Na⁺ transport in liposomes has been demostrated (Soontharapirakkul and Incharoensakdi 2010). The enzyme appears to play a role in salt tolerance (Soontharapirakkul et al. 2011). This halotolerant cyanobacterium has both a Na⁺- and a H⁺-pumping ATPase (see TC# 3.A.2.1.10). The sequence of the δ-subunit was not available at the time of entry. The phototroph-specific beta-hairpin structure of the gamma subunit of FoF1-ATP synthase is important for efficient ATP synthesis in cyanobacteria (Kondo et al. 2021). ATP is an inhibitor of the F₀F₁-ATP synthase to arrest ATP hydrolysis during low-energy conditions in cyanobacteria (Song et al. 2022).