Diphosphate—fructose-6-phosphate 1-phosphotransferase also known as PFP is an enzyme of carbohydrate metabolism in plants and some bacteria. The enzyme () catalyses the reversible interconversion of fructose 6-phosphate and fructose 1,6-bisphosphate using inorganic pyrophosphate as the phosphoryl donor:
:diphosphate + D-fructose 6-phosphate <math>\rightleftharpoons</math> phosphate + D-fructose 1,6-bisphosphate
In plants, the PFP is located in the cytosol of the cell and is strongly activated by the signal molecule fructose 2,6-bisphosphate.
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Image:Beta-D-fructose-6-phosphate wpmp.png|Fructose 6-phosphate
Image:Beta-D-fructose-1,6-bisphosphate wpmp.png |Fructose 1,6-bisphosphate
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PFP is an exclusively cytosolic enzyme that catalyses the phosphorylation of fructose-6-phosphate to fructose-1,6-bisphosphate in the glycolytic direction, and the de-phosphorylation of fructose-1,6-bisphosphate to fructose-6-phosphate in the gluconeogenic reaction. Reeves first isolated PFP from Entamoeba histolytica, a lower eukaryote. The first plant PFP isolated was from the leaves of pineapples by Carnal and Black and it has since been isolated from a variety of plant species and tissues.
Nomenclature
This enzyme belongs to the family of transferases, specifically those transferring phosphorus-containing groups (phosphotransferases) with an alcohol group as acceptor. The systematic name of this enzyme class is diphosphate:D-fructose-6-phosphate 1-phosphotransferase. Other names in common use include:
- 6-phosphofructokinase (pyrophosphate),
- inorganic pyrophosphate-dependent phosphofructokinase,
- inorganic pyrophosphate-phosphofructokinase,
- pyrophosphate-dependent phosphofructo-1-kinase, and
- pyrophosphate-fructose 6-phosphate 1-phosphotransferase,
- pyrophosphate-fructose 6-phosphate phosphotransferase
See also
- PFK