56 by: Owen Robertson

Student – Owen Robertson

Enzyme & EC # – Phosphofructokinase, EC:2.7.1.11

PFK is found in the tissues of mammals, more precisely the liver (PFK-L), muscles (PFK-M), and in the platelets (PFK-P).

PFK is an allosteric enzyme that catalyzes the rate limiting step in glycolysis in mammals. It catalyzes the phosphorylation of fructose-6-phosphate into fructose-1,6-phosphate with a few amino acids to stabilize the reaction and is controlled by ATP so that when the cell has enough energy stored it won’t break down any more glucose. It is important for it to be regulated as once the phosphorylation happens it is irreversible, which would be a waste to keep breaking down glucose for cell energy when it is not needed.

PFK is a member of the Ribokinase family along with ribokinase, adenosine kinase, and inosine kinase. A lack of phosphofructokinase lead to a disease called Tarui’s disease which is a disorder that has severe side effects of nausea, vomiting, and muscle cramps when high intensity activities such as running or sports are being played.

References

Cole, A. S., & Eastoe, J. E. (1988). The integration and control of metabolism. Biochemistry and Oral Biology, 329–344. https://doi.org/10.1016/b978-0-7236-1751-8.50030-2

Glycolysis. Physiopedia. (n.d.). https://www.physio-pedia.com/Glycolysis#:~:text=Glycolysis%20is%20important%20because%20it,red%20blood%20cells%20can%20use

Group, T. (n.d.). Mechanism and catalytic site Atlas. M-CSA Mechanism and Catalytic Site Atlas. https://www.ebi.ac.uk/thornton-srv/m-csa/entry/365/