The F1 genes of the F1F0 ATP synthase from the acidophilic bacterium Thiobacillus ferrooxidans complement Escherichia coli F1 unc mutants.

An atp gene cluster from the extreme acidophile Thiobacillus ferrooxidans was able to complement Escherichia coli F1 unc mutants for growth on minimal medium plus succinate. Complementation with all four E. coli F1 mutants tested was observed and subunits for the F1 portion of the T. ferrooxidans ATP synthase formed a functional association with the F0 subunits of the E. coli enzyme. In addition, a hybrid F1 enzyme in which some units were derived from E. coli and some from T. ferrooxidans was partially functional. No clones capable of complementing E. coli F0 unc mutants were isolated. The nucleotide sequence of the gene cluster was determined and the genes for the F0 and the F1 ATP synthase subunits were found to be physically linked.