X-Ray Energy Dispersive Analysis of Polyphosphate Bodies in Plectonema boryanum

Polyphosphate bodies are one of several types of storage inclusions which are commonly found in microorganisms. They may be induced by various metabolic conditions, the most common of which are nutrient imbalance and disturbance of nucleic acid metabolism. Polyphosphate bodies are found in large numbers in cells that have been subjected to conditions of low available phosphate and then reinoculated into a medium containing phosphate. This phenomenon has been referred to by a variety of terms such as “rapid uptake”, the polyphosphate “overplus” phenomenon, and luxury storage. The polyphosphate bodies are osmotically inert long chain inorganic polymers. The exact chemical composition has, as yet, been difficult to ascertain. Chain length of the phosphate polymer can be analyzed by chromatography. However, only a few reports of polyphosphate bodies in protozoa have indicated that calcium and magnesium are constituents of the salt.