Sarcocystis fusiformis: some Krebs cycle enzymes in various fractions of sarcocysts of buffalo (Bubalus bubalis).

A biochemical investigation was carried out on the relative presence of some enzymes of the Krebs cycle and of the associated energy metabolism in various fractions (namely, cyst wall, cyst fluid and zoites) of sarcocysts of Sarcocystis fusiformis from the oesophageal muscles of naturally infected Indian water buffalo (Bubalus bubalis). Except for malate dehydrogenase, the activities of aconitase, isocitrate dehydrogenase, succinate dehydrogenase and fumarase were beyond detectable limits, pointing to a non-functional Krebs cycle in the cysts of this parasite. The activities of adenosine triphosphatase and cytochromes were lowest in cyst fluid and were maximally depicted by cyst wall and zoites.