Km of phosphofructokinase-2 for ATP

Value 42 µM
Organism Bacteria Escherichia coli
Reference Baez M, Rodríguez PH, Babul J, Guixé V. Structural and functional roles of Cys-238 and Cys-295 in Escherichia coli phosphofructokinase-2. Biochem J. 2003 Nov 15 376(Pt 1):277-83PubMed ID12927023
Method ATP and fru-6-P concentrations were estimated spectrophotometrically by measuring the amount of fru-1,6-bisP formed in the presence of NADH, using aldolase, triosephosphate isomerase and a-glycerophosphate dehydrogenase as auxiliary enzymes. PFK activity was determined spectrophotometrically by coupling the fru-1,6-bisP formation to the oxidation of NADH as described previously [5].
Comments Phosphofructokinase (PFK, EC. is a central enzyme of glycolysis and is found in almost all organisms, from bacteria to higher eukaryotes. Owing to its important role in the control of glycolytic flux and its allosteric properties, PFK has long been a subject of study in terms of both its enzymology and protein chemistry. The enzyme catalyses the conversion of fructose 6- phosphate (fru-6-P) into fructose 1,6-bisphosphate (fru-1,6-bisP), with associated consumption of ATP. In Escherichia coli, two different enzymes catalyse this reaction: a Pfk-1,which represents 90% of the total activity and Pfk-2, which accounts for the rest.
Entered by Uri M
ID 104957