Preparation of monoclonal antibodies against chicken liver 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase and their effects on enzyme activities.
The effects of the monoclonal antibodies (McAbs) directed against chicken liver 6-phosphofructo-2-kinase/fructose-2, 6-bisphosphatase (6PF-2-K/Fru-2, 6-P2ase) on the structure and function of the enzyme were studied. Using chicken liver 6PF-2-K/Fru-2, 6-P2ase as antigen, 7 clones of monoclonal antibodies specifically binding with the antigen were obtained. The epitopes of the antigen recognized by the 6 McAbs localized on the fructose-2, 6-bisphosphatase domain of chicken liver 6PF-2-K/Fru-2, 6-P2ase, and the other (H2) are on the 6-phosphofructo-2-kinase domain. All of the 7 McAbs could activate the kinase activity of the bifunctional enzyme by twofold and had a similar effect on the bisphosphatase activity of the bifunctional enzyme which resulted in a fourfold increase of the bisphosphatase activity of the bifunctional enzyme. However, the McAbs did not affect the activity of the separated fructose-2, 6-bisphosphatase domain. The results suggested that the Fru-2, 6-P2ases in the bifunctional enzyme and in the separated bisphosphatase domain were in two different conformation and activity states.
Li
T
T
Shanghai Institute of Biochemistry, Chinese Academy of Sciences, China.
Ding
J
J
Li
L
L
Xu
G
G
D000818:Animals; D000911:Antibodies, Monoclonal / Q000096:biosynthesis / Q000276:immunology*; D005260:Female; D006597:Fructose-Bisphosphatase / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D009097:Multienzyme Complexes / Q000276:immunology*; D010732:Phosphofructokinase-1 / Q000276:immunology*; D025481:Phosphofructokinase-2; D010744:Phosphoric Monoester Hydrolases / Q000378:metabolism; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000378:metabolism
D000911:Antibodies, Monoclonal; D009097:Multienzyme Complexes; D017853:Phosphotransferases (Alcohol Group Acceptor); D025481:Phosphofructokinase-2; D010732:Phosphofructokinase-1; D006597:Fructose-Bisphosphatase; D010744:Phosphoric Monoester Hydrolases