Imidonitrogen in chlorella "polyphosphate".

"Polyphosphate" and fragments isolated from acid hydrolysis of polyphosphate have an infrared absorption band at 1400 cm(-1), which is characteristic of imidodiphosphate linkages. Complete hydrolysis of purified "polyphosphate" releases 1 to 2 moles of phosphate per mole of ammonia. The polymer must contain subunits which are cyclic and which contain both imidodiphosphate linkages and phosphate anhydride linkages.