Statistical analysis of F/V-ATPase tree topology. The schematic shows the constraints on the tree topology and the results of the AU-test in comparison to the unconstrained tree. Red branches denote (predicted) Na+-dependent ATPases, and blue branches denote (predicted) H+-dependent ATPases. The corresponding AU-test p-value is shown for each constrained topology; trees with p-values < 0.05 are rejected (crossed frame). a. monophyly of all Na+-dependent and H+-dependent enzymes regardless of the type (F or V); b. monophyly of Na+-dependent and H+-dependent enzymes within V-ATPase and F-ATPase clades each; c. Na+-dependent V-ATPases paraphyletic to monophyletic H+-dependent V-ATPases; F-ATPases unconstrained; d. both Na+-dependent and H+-dependent V-ATPases monophyletic; F-ATPases unconstrained; e. H+-dependent V-ATPases paraphyletic to monophyletic Na+-dependent V-ATPases; F-ATPases unconstrained; f. Na+-dependent F-ATPases paraphyletic to monophyletic H+-dependent F-ATPases; V-ATPases unconstrained; g. both Na+-dependent and H+-dependent F-ATPases monophyletic; V-ATPases unconstrained; h. H+-dependent F-ATPases paraphyletic to monophyletic Na+-dependent F-ATPases; V-ATPases unconstrained.