Abstract
Plant mitochondrial ATPase has been chloroform-solubilized and purified by gel filtration from spadices of cuckoo-pint (Arum maculatum). The subunit composition of purified plant and rat liver ATPase were compared by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis. The delta- and epsilon-subunits of the plant enzyme are larger than their supposed rat liver counterparts and, as such, A. maculatum mitochondrial ATPase shows structural homologies with the enzyme from Escherichia coli [Futai, Sternweis & Heppel (1974) Proc. Natl. Acad. Sci. U.S.A. 71, 2725-2729] rather than with the rat liver enzyme.