Molecular Cloning and Sequencing of Plasma Membrane H⁺-ATPase Gene from the Salt-Tolerant Yeast Zygosaccharomyces rouxii

Abstract

A plasma membrane H⁺-ATPase gene from the salt-tolerant yeast Zygosaccharomyces rouxii was isolated by probing the genomic DNA library with a labeled DNA fragment derived from the Saccharomyces cerevisiae H⁺-ATPase gene (PMA1) and the nucleotide sequence of a cloned gene was determined. The gene encoded a polypeptide of molecular weight 100, 060 that consisted of 920 amino acid residues. The deduced amino acid sequence was 83% homologous to that of S. cerevisiae H⁺-ATPase and was highly similar to the conserved sequences in the plasma membrane ATPase family comprising yeast plasma membrane H⁺-ATPases. The peptide motifs involved in the ATPase functions were found in the Z. rouxii H⁺-ATPase sequence. The result of Northern analysis indicated that the size of the transcript of the Z. rouxii H⁺-ATPase gene was the same as that of S. cerevisiae PMA1.