[Roles of anions in cells: studies on a Cl(-)-translocating ATPase and sulfate uptake system in Acetabularia acetabulum].

Biochemical and molecular biological approaches to two anion translocators, a Cl(-)-translocating ATPase and sulfate permease were described for Acetabularia acetabulum, a unicellular marine alga. The primary structures of an almost complete cDNA clone of the 50 kDa subunit and a partial cDNA clone of the 54 kDa subunit of the Cl(-)-ATPase were highly similar to the beta and alpha subunits of the F type ATPase, respectively. A partial cDNA clone encoding the alpha subunit of chloroplast ATPase, and partial cDNA clones coding for the beta subunits of chloroplast and mitochondrial ATPases were also obtained from A. acetabulum. The presence of a small multigene family for the F type ATPases with different ion specificities was strongly suggested for the organism. Sulfate uptake system in this organism was also studied and partial cDNA clones encoding CysA and sulfate binding proteins were obtained. ca. 1.7 kb RNA for cysA gene and 1.55 kb for sbp gene were detected by Northern analysis, respectively. A putative malK gene was also partially cloned.