Phosphofructokinase 1

Phosphofructokinase 1

Protbox
Name=Phosphofructokinase
Photo=Phosphofructokinase 6PFK wpmp.pngCaption=
Gene_type=protein coding
Molecular_weight= 82,000
Structure=
Type=Enzyme: Kinase
Functions=converts fructose 6-phosphate + ATP to fructose 1,6-bisphosphate + ADP
Domains=
Motifs=
Alternative_products=
Catalytic_activity=
Cofactors=
Enzyme_regulation=
Diseases=
Pharmaceuticals=
Taxa=
Cells= ubiquitous
Location=
Names=
Pathways=Citric acid cycle, Glycolysis
Interactions=
Pages=
Review=
ECnumber=2.7.1.11
Names=6-Phosphofructokinase, 6-Phosphofructo-1-kinase, Fructose-6-P 1-Kinase, Fructose-6-phosphate 1-Phosphotransferase

[
http://www.pdb.org/pdb/static.do?p=education_discussion/molecule_of_the_month/pdb50_4.html more details...] )] Phosphofructokinase-1 (PFK-1) is the most important regulatory enzyme (EC number|2.7.1.11) of glycolysis. It is an allosteric enzyme made of 4 subunits and controlled by several activators and inhibitors. PFK-1 catalyzes one of the important "committed" steps of glycolysis, the conversion of fructose 6-phosphate and ATP to fructose 1,6-bisphosphate and ADP. Enzymatic Reaction
foward_enzyme=Phosphofructokinase-1
reverse_enzyme=Fructose bisphosphatase
substrate=α-D-fructose 6-phosphate
product=α-D-fructose 1,6-bisphosphate
reaction_direction_(foward/reversible/reverse)=reversible
minor_foward_substrate(s)=ATP
minor_foward_product(s)=ADP
minor_reverse_substrate(s)=H2O
minor_reverse_product(s)=Pi
substrate_

product_

This step is subject to extensive regulation since it is not only irreversible, but also because the original substrate is forced to proceed down the glycolytic pathway after this step. This leads to a precise control of glucose and the other monosaccharides galactose and fructose going down the glycolysis pathway. Before this enzyme's reaction, glucose-6-phosphate can potentially travel down the pentose phosphate pathway, or be converted to glucose-1-phosphate and polymerized into the storage form Glycogen.

Regulation

PFK1 is allosterically inhibited by ATP and citrate (from the citric acid cycle) and its product. It is also inhibited by low pH to prevent the accumulation of hydrogen ions in muscle. The enzyme has two sites with different affinities for ATP which is both a substrate and an inhibitor.

PFK1 is allosterically activated by a high concentration of AMP, but the most potent activator is fructose 2,6-bisphosphate, which is also produced from fructose-6-phosphate by PFK2.

PFK is inhibited by glucagon through repression of synthesis.

The precise regulation of PFK 1 prevents glycolysis and gluconeogenesis from occurring simultaneously.

Genes

There are three phosphofructokinase genes in humans:
* - liver
* - muscle
* - platelet

ee also

*PFK2 (converts fructose 6-phosphate to fructose 2,6-bisphosphate through on site, or the opposite, on another site)
*PFP (reversibly interconverts fructose 6-phosphate and fructose 1,6-bisphosphate using inorganic pyrophosphate (rather than ATP)
*fructose bisphosphatase (hydrolyses fructose 1,6-bisphosphate to fructose 6-phosphate)

External links

*


Wikimedia Foundation. 2010.

Look at other dictionaries:

  • Phosphofructokinase — Bezeichner …   Deutsch Wikipedia

  • Phosphofructokinase 1 — Masse/Länge Primärstruktur 780 Aminosäuren …   Deutsch Wikipedia

  • Phosphofructokinase-1 —   N° EC …   Wikipédia en Français

  • Phosphofructokinase-2 — Structure de la 6 phosphofructo 2 kinase : à droite, le domaine phosphatase ; à gauche …   Wikipédia en Français

  • Phosphofructokinase 2 — Phosphofructokinase 2/ Fructose 2,6 bisphosphatase Bänder /Oberflächenmodell des Dimer. Die PFK Domäne ist blau, die FB Domän …   Deutsch Wikipedia

  • Phosphofructokinase — La phosphofructokinase (EC 2.7.1.11)(PFK) est une enzyme qui catalyse la transformation de fructose 6 phosphate en fructose 1 6 bisphosphate dans les phénomènes physiologiques de glycolyse. Fructose 6 phosphate → Fructose 1,6 di(bi)phosphate L… …   Wikipédia en Français

  • Phosphofructokinase 2 — (PFK2) is one activity of a bifunctional enzyme (EC number|2.7.1.105), the other of which is fructose 2,6 bisphosphatase (FBPase2). When serine 32 is phosphorylated, the negative charge causes the conformation of the enzyme to favor the FBPase2… …   Wikipedia

  • Phosphofructokinase — PFK redirects here. PFK (Poulet Frit Kentucky) is also the name for KFC in French speaking Quebec, Canada. For the Polish hip hop group, see Paktofonika. Phosphofructokinase Identifiers Symbol Ppfruckinase Pfam …   Wikipedia

  • phosphofructokinase 1 — phos·pho·fruc·to·ki·nase 1 (fos″fo frook″to kiґnās) 6 phosphofructokinase …   Medical dictionary

  • phosphofructokinase — noun Etymology: phosph + fructose + kinase Date: 1947 an enzyme that functions in carbohydrate metabolism and especially in glycolysis by catalyzing the transfer of a second phosphate (as from ATP) to fructose …   New Collegiate Dictionary

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”