FIG. 2.

ACU ATPases are typical P-type ATPases. Alignment of the translated sequences of the U. maydis acu1 and acu2 and P. sorbitophila ACU1 genes with the sequences of one animal Na⁺,K⁺-ATPase and one fungal ENA-ATPase. Conserved segments and the 10 putative transmembrane fragments of P-type ATPases (2, 33) are shown in black boxes and underlined, respectively. Amino acids which are essential for the binding of K⁺ or Na⁺ and for Na⁺ or K⁺ selectivity in Na⁺,K⁺-ATPases (30) are shown in grey. Accession numbers: NaKRat, M14511.1; ScENA1, P13587.