12.31 Phosphorus Functions

Phosphorus has a number of functions in the body.

Phosphate is a component of hydroxyapatite in bones and teeth, as described earlier.

Non-bone functions include:


Phosphates are used to activate and deactivate a number of proteins. In addition, compounds are also frequently phosphorylated, like the monosaccharides shown below.

Figure 12.311 Uptake of monosaccharides into the hepatocyte1


Phosphates are a component of phospholipids, as shown below.

Figure 12.312 Structure of phosphatidylcholine (lecithin)2


DNA/RNA have a phosphate backbone as shown below.

Figure 12.313 Structure of DNA3


The major energy currency, ATP, stores energy in its phosphate bonds.

Figure 12.314 Structure of ATP4

Secondary Messengers

The intracellular secondary messengers cyclic AMP (cAMP) and inositol triphosphate (IP3) both contain phosphate. The action of these secondary messengers can be seen in the links below.

Web Links



Other functions of phosphate include:

Acid/Base Balance

Intracellular Anion

References & Links

1. Gropper SS, Smith JL, Groff JL. (2008) Advanced nutrition and human metabolism. Belmont, CA: Wadsworth Publishing.

2. http://commons.wikimedia.org/wiki/File:Popc_details.svg

3. http://en.wikipedia.org/wiki/File:DNA_chemical_structure.svg

4. http://en.wikipedia.org/wiki/File:ATP_structure.svg


cAMP – http://courses.washington.edu/conj/gprotein/cyclicamp.htm

IP3 – http://courses.washington.edu/conj/gprotein/ip3.htm