Pyrophosphate Identifiers PubChem ChemSpider DrugBank ChEBI Jmol-3D images Image 1 Properties Molecular formula P2O74− (what is: /?)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
In chemistry, the anion, the salts, and the esters of pyrophosphoric acid are called pyrophosphates. Any salt or ester containing two phosphate groups is called a diphosphate. As a food additive, diphosphates are known as E450.
Pyrophosphates were originally prepared by heating phosphates (pyro- from the Greek, meaning fire). Pyrophosphates are good complexing agents and have many uses in industrial chemistry. Pyrophosphate is the first member of an entire series of polyphosphates.
The term pyrophosphate is also the name of esters formed by the condensation of a phosphorylated biological compound with inorganic phosphate as for dimethylallyl pyrophosphate. This bond is also referred to as a high-energy phosphate bond.
The synthesis of tetraethyl pyrophosphate was first described in 1854 by Philip de Clermount at a meeting of the French Academy of Sciences.
- ATP → AMP + PPi
For example, when a nucleotide is incorporated into a growing DNA or RNA strand by a polymerase, pyrophosphate (PPi) is released. Pyrophosphorolysis is the reverse of the polymerization reaction in which pyrophosphate reacts with the 3'-nucleotidemonophosphate (NMP or dNMP), which is removed from the oligonucleotide to release the corresponding triphosphate (dNTP from DNA, or NTP from RNA).
- P2O74− + H2O → 2 HPO42−
or in biologists' shorthand notation:
- PPi + H2O → 2 Pi
In the absence of enzymic catalysis, hydrolysis reactions of simple polyphosphates such as pyrophosphate, linear triphosphate, ADP, and ATP normally proceed extremely slowly in all but highly acidic media.
(The reverse of this reaction is a method of preparing pyrophosphates by heating phosphates.)
This hydrolysis to inorganic phosphate effectively renders the cleavage of ATP to AMP and PPi irreversible, and biochemical reactions coupled to this hydrolysis are irreversible as well.
PPi occurs in synovial fluid, blood plasma, and urine at levels sufficient to block calcification and may be a natural inhibitor of hydroxyapatite formation in extracellular fluid (ECF). Cells may channel intracellular PPi into ECF. ANK is a nonenzymatic plasma-membrane PPi channel that supports extracellular PPi levels. Defective function of the membrane PPi channel ANK is associated with low extracellular PPi and elevated intracellular PPi. Ectonucleotide pyrophosphatase/phosphodiesterase (ENPP) may function to raise extracellular PPi.
From the standpoint of high energy phosphate accounting, the hydrolysis of ATP to AMP and PPi requires two high-energy phosphates, as to reconstitute AMP into ATP requires two phosphorylation reactions.
- AMP + ATP → 2 ADP
- 2 ADP + 2 Pi → 2 ATP
- Adenosine monophosphate
- Adenosine diphosphate
- Adenosine triphosphate
- ATP hydrolysis
- ATP synthase
- Calcium pyrophosphate
- Calcium pyrophosphate dihydrate deposition disease
- High energy phosphate
- Inorganic pyrophosphatase
- List of biochemical phosphate reactions
- List of human ATPase genes
- Nucleoside triphosphate
- Oxidative phosphorylation
- Phosphate homeostasis
- Phosphate reaction
- Phosphoric acid
- Phosphoric acids and phosphates
- Ribonucleoside monophosphate
- Sodium pyrophosphate
- Structural phosphate
- Thiamine pyrophosphate
- Zinc pyrophosphate
- ^ Huebner PWA, Milburn RM (May 1980). "Hydrolysis of pyrophosphate to orthophosphate promoted by cobalt(III). Evidence for the role of polynuclear species". Inorg Chem. 19 (5): 1267–72. doi:10.1021/ic50207a032.
- ^ a b Ho AM, Johnson MD, Kingsley DM (Jul 2000). "Role of the mouse ank gene in control of tissue calcification and arthritis". Science. 289 (5477): 265–70. doi:10.1126/science.289.5477.265. PMID 10894769.
- ^ a b c Rutsch F, Vaingankar S, Johnson K, Goldfine I, Maddux B, Schauerte P, Kalhoff H, Sano K, Boisvert WA, Superti-Furga A, Terkeltaub R (Feb 2001). "PC-1 nucleoside triphosphate pyrophosphohydrolase deficiency in idiopathic infantile arterial calcification". Am J Pathol. 158 (2): 543–54. doi:10.1016/S0002-9440(10)63996-X. PMC 1850320. PMID 11159191. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1850320.
- Schröder HC, Kurz L, Muller WEG, Lorenz B (Mar 2000). "Polyphosphate in bone". Biochemistry (Moscow). 65 (3): 296–303. http://protein.bio.msu.su/biokhimiya/contents/v65/pdf/bcm_0296.pdf.
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pyrophosphate — [ pirofɔsfat ] n. m. • 1842; de pyro et phosphate ♦ Chim. Sel de l acide pyrophosphorique. ● pyrophosphate nom masculin Sel de l acide pyrophosphorique. pyrophosphate [piʀofɔsfat] n. m. ÉTYM … Encyclopédie Universelle
Pyrophosphate — Pyr o*phos phate, n. (Chem.) A salt of pyrophosphoric acid. [1913 Webster] … The Collaborative International Dictionary of English
pyrophosphate — [pī΄rə fäs′fāt΄] n. a salt or ester of pyrophosphoric acid … English World dictionary
Pyrophosphate — Anion pyrophosphate ou PPi Les pyrophosphates (appelés aussi diphosphates) sont l anion (base conjuguée), les sels et les esters de l acide pyrophosphorique. Les pyrophosphates sont constitués de deux molécules de phosphates condensées. Ils sont… … Wikipédia en Français
Pyrophosphate — Diphosphat Anion Diphosphate (auch Pyrophosphate (PPa; engl.: PPi)) sind Salze und Ester der Diphosphorsäure H4P2O7. Diphosphate sind Kondensate von zwei Phosphaten. Sie sind über eine P–O–P Säureanhydrid Bindung miteinander verknüpft ( … Deutsch Wikipedia
pyrophosphate — ortodifosfatas statusas T sritis chemija formulė M₄P₂O₇ atitikmenys: angl. orthodiphosphate; pyrophosphate rus. ортодифосфат; пирофосфат ryšiai: sinonimas – μ ( okso( )heptaoksodifosfatas (4–) … Chemijos terminų aiškinamasis žodynas
pyrophosphate — noun a salt or ester of pyrophosphoric acid • Hypernyms: ↑salt * * * /puy reuh fos fayt/, n. Chem. a salt or ester of pyrophosphoric acid. [1830 40; PYROPHOSPH(ORIC ACID) + ATE2] * * * pyrophosphate noun see above • • • Main Entry: ↑pyro … Useful english dictionary
pyrophosphate — noun Date: 1833 a salt or ester of pyrophosphoric acid … New Collegiate Dictionary
pyrophosphate — /puy reuh fos fayt/, n. Chem. a salt or ester of pyrophosphoric acid. [1830 40; PYROPHOSPH(ORIC ACID) + ATE2] * * * … Universalium
pyrophosphate — noun Any salt or ester of pyrophosphoric acid … Wiktionary