diphosphateglucuronosyltransferase

Diphosphate, commonly called pyrophosphate, is the dianion or salt form of pyrophosphoric acid. It consists of two phosphate units connected by an anhydride linkage, giving the formula P2O7^4− in its fully deprotonated state. In solution, multiple protonation states exist depending on pH.

Biological role and metabolism: Pyrophosphate is produced during condensation reactions, such as the polymerization of nucleotides, where the incorporation of a nucleotide releases pyrophosphate (PPi). The hydrolysis of PPi to two inorganic phosphate (Pi) by inorganic pyrophosphatases helps drive biosynthetic reactions forward, coupling metabolism to energy release and enabling unfavored steps to proceed.

Chemical properties and reactivity: Pyrophosphate is highly anionic and can act as a chelating agent for metal ions. It participates in buffer systems under suitable pH ranges and is susceptible to hydrolysis, particularly under acidic conditions or in the presence of catalysts, yielding inorganic phosphate.

Occurrence and applications: Pyrophosphate salts are used in food processing as leavening agents and sequestrants, and in detergents as water-softening agents. In molecular biology, PPi is a key byproduct of nucleotide incorporation during nucleic acid synthesis and is often measured in enzymatic assays. Within cells, PPi is rapidly hydrolyzed to two Pi, helping to drive biosynthetic pathways.

Safety and regulation: Pyrophosphate salts are widely used and regulated as food additives (sometimes listed as E450). High concentrations can irritate mucous membranes or cause gastrointestinal discomfort; appropriate handling and dosing are advised.

Note: If the intended topic was a different compound involving two phosphate groups linked to a glucose or amino acid moiety (for example diphosphoglucose or diphosphoglutamate), please provide the exact term for a targeted article.