title: The appearance of a critical input concentration of fructose 6-phosphate in the 6-phosphofructo-2-kinase/fructose 2,6-bisphosphatase cycle.
abstract: Stationary states of the fructose 6-phosphate/fructose 2,6-bisphosphate cycle were investigated in relation to the input concentration of fructose 6-phosphate. Below a critical input concentration of fructose 6-phosphate very low levels of fructose 2,6-bisphosphate were obtained. Above this point the fructose 2,6-bisphosphate changes in direct proportion to the input of fructose 6-phosphate. Phosphorylation of the enzyme causes an increase of the critical input concentration of fructose 6-phosphate. The control coefficients for fructose 2,6-bisphosphate have their maximum at the critical input concentration of fructose 6-phosphate.
authors.affiliation: Institute of Biochemistry, Karl-Marx-University, Leipzig, German Democratic Republic.
authors.forename: M
authors.initials: M
authors.lastname: Kretschmer
authors.forename: W
authors.initials: W
authors.lastname: Schellenberger
authors.forename: E
authors.initials: E
authors.lastname: Hofmann
mesh_terms: D005636:Fructosephosphates / Q000378:metabolism*; D007700:Kinetics; D025481:Phosphofructokinase-2; D010744:Phosphoric Monoester Hydrolases / Q000378:metabolism*; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000378:metabolism*
chemical_list: D005636:Fructosephosphates; C027618:fructose-6-phosphate; D017853:Phosphotransferases (Alcohol Group Acceptor); D025481:Phosphofructokinase-2; D010744:Phosphoric Monoester Hydrolases