RESPIRATION OF A RICKETTSIALIKE MICROORGANISM, WOLBACHIA PERSICA*

Shortly after its isolation from the Malpighian tubules of a soft tick, Argas persicus (Oken), it was realized that Wolbachia persica did not closely resemble any other well characterized microorganism (Suitor and Weiss, 1961). It was called rickettsial ike and placed in the genus Wolbachia because of basic similarities in ecology and size to the known rickettsiae and also because of its inability to grow on cell-free mediums. In its morphology and pattern of growth it did not closely resemble either a rick-ettsia or a bedsonia. t Studies of the metabolic activities of rickettsiae in an extracellular environ-ment, initiated by Bovarnick and Snyder (1949), have provided excellent characterization of these microorgan-isms. It has been shown that rickettsiae possess some of the enzyme systems of bacteria, and they are now regarded as bacterium-like rather than virus-like (review by Weiss, 1960). Bedsoniae, studied under similar conditions, did not display the activities of rickettsia