Non-mitochondrial ATP transport

Exchange of organelle ATP with cytosolic ADP through the ADP/ATP carrier is a well-characterized feature of mitochondrial metabolism. Obligate intrace llular bacteria, such as Rickettsia prowazekii, and higher-plant plastids p ossess another type of adenylate transporter, which exchanges bacterial or plastidic ADP for ATP from the eukaryotic (host cell) cytoplasm. The bacter ial and plastidic transporters are similar but do not share significant seq uence similarities with the mitochondrial carrier. Recent molecular and bio chemical studies are providing deeper insight into the functional and evolu tionary relationships between the bacterial and the plant transport protein s.