This family consists of the C-terminal domain of several bacterial Na(+)-translocating NADH-quinone reductase subunit A (NQRA) proteins. The Na(+)-translocating NADH: ubiquinone oxidoreductase (Na(+)-NQR) generates an electrochemical Na(+) potential driven by aerobic respiration [1].

1: Sequencing and preliminary characterization of the Na+-translocating NADH:ubiquinone oxidoreductase from Vibrio harveyi. Zhou W, Bertsova YV, Feng B, Tsatsos P, Verkhovskaya ML, Gennis RB, Bogachev AV, Barquera B; Biochemistry 1999;38:16246-16252. PMID:10587447