Pyruvate metabolism by Anaplasma marginale in cell-free culture

Partially purified Anaplasma marginale initial bodies were cultivated in a cell-free system in the presence of [3-C-14]pyruvate for 24 or 48 h. Experi ments showed that a significant portion of the pyruvate supplied to the cul tures was incorporated into initial body components. Label incorporation wa s reduced by 72% in the presence of oxytetracycline. Fractionation and chro matography of the organisms revealed radioactive incorporation as alanine. This is the first report of de novo amino acid synthesis by A. marginale de monstrating that the rickettsia is capable of using pyruvate, an erythrocyt e glycolytic product, in its metabolism.