Polyphosphates are
salts or
esters of polymeric
oxyanions formed from
tetrahedral PO
4 (
phosphate) structural units linked together by sharing oxygen atoms. Polyphosphates can adopt linear or a cyclic ring structures. In biology, the polyphosphate esters
ADP and
ATP are involved in energy storage. A variety of polyphosphates find application in mineral sequestration in municipal waters, generally being present at 1 to 5 ppm.
GTP,
CTP, and
UTP are also nucleotides important in the protein synthesis, lipid synthesis, and carbohydrate metabolism, respectively.