User:Jglundgr/sandbox

Function
Polyphosphates are utilized by exopolyphosphatase enzymes, which cleave portions of the chain of phosphates. These proteins play an essential role in the metabolism and maintenance of polyphosphates. Polyphosphate is located throughout the cytosol of each cell and is also present in the cell's organelles. There are many classes of exopolyphosphatases, each with their own unique localization and properties. It has been speculated that once the polyphosphates are broken down, they are involved with signaling molecules acting as secondary messengers. In E. coli, the regulation of polyphosphate metabolism is poorly understood.

Polyphosphate is a linear chain of phosphates linked together by phosphoanhydride bonds. Polyphosphate is found in all living organisms and plays an essential role in the organisms survival. In bacteria, polyphosphate is used to store energy to replace adenosine triphosphate. It has also been shown to be involved with cell membrane formation and function, enzyme regulation, and gene transcriptional control. In mammals, polyphosphates are involved with blood coagulation and inflammation, immune response, bone tissue development, and brain function.

It has been shown in a yeast model that mutant yeast deficient in exopolyphosphatase activity had problems in respiration functions and metabolism of inorganic polyphosphates. Conversely, yeast strains that have higher levels exopolyphosphatase enzyme are shown to have no obvious growth defects under phosphate deficiency or excess phosphate conditions, however the level of polyphosphate in the yeast was much lower due to the increased number of enzymes breaking the polyphosphate chains down. .