phosphate groupmedical dictionary

<chemistry> A phosphate group on a larger molecule, where the phosphorus is single bonded to each of the four oxygens, and the other bond of one of the oxygens is attached to the rest of the molecule.

This means that the entire group has a net negative charge of -3 (from the free second bonds on the oxygen atoms which are only bonded to the phosphorus atom). Often hydrogen atoms will be attached to the oxygens and sometimes double bonds between the phosphorus and an oxygen are present.

(31 Dec 1997)