THE NA+-TRANSLOCATING ATPASE OF ACETOBACTERIUM-WOODII IS A F1F0-TYPE ENZYME AS DEDUCED FROM THE PRIMARY STRUCTURE OF ITS BETA-SUBUNITS, GAMMA-SUBUNITS AND EPSILON-SUBUNITS

A 4.5 kbp EcoRI fragment hybridizing to a fragment of uncD (coding for subunit beta of F1F0-ATPases) was cloned from chromosomal DNA of Acetobacterium woodii. The nucleotide sequence was determined and revealed five open reading frames (ORF), four of which were identified to code for subunits of the Na+-ATPase. The deduced amino acid sequences of these ORF's are homologous to subunit alpha (partial coding sequence, C-terminal end), gamma, beta and epsilon of F1F0-ATPases from various organisms; furthermore, the organization of the genes in the order uncA (alpha), uncG (gamma), uncD (beta), uncC (epsilon) is identical to the structure of une operon as present in most bacteria. Downstream of uncC is an ORF whose deduced amino acid sequence has 53% sequence homology to AlgD from Pseudomonas aeruginosa. The structure and organization of the une genes are the final proof that the Na+-ATPase from A. woodii is a member of the family of F1F0-ATPases.