Studies on the phosphorylation of muscle phosphofructokinase.

Kemp, Robert G.; Foe, Lawrence G.; Latshaw, Steven P.; Poorman, Roger A.; Heinrikson, Robert L.

doi:10.1016/s0021-9258(19)68959-3

Cited by 60 publications

(13 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It has also to be pointed out that the concentration of phosphofructokinase in the phosphorylation reaction was less than 1 UM, because of the small amounts of purified enzyme available. This is very low compared with the reported values of the apparent Km of cyclic AMPdependent protein kinase for skeletal-muscle and liver phosphofructokinase of 100-250 /tM (Kemp et al, 1981;Pilkis et al, 1982), and this may be the principal reason for the less than stoichiometric incorporation of 32P into whiteor brown-adipose-tissue phosphofructokinase in the present studies.…”

Section: Discussioncontrasting

confidence: 81%

“…However, an alternative hypothesis would be that the persistent changes in kinetic properties were the result, at least in part, of an increase in phosphorylation of the enzyme by cyclic AMP-dependent protein kinase. Phosphofructokinase from a number of different sources has been shown to be a substrate for cyclic AMP-dependent protein kinase, including liver (Furuya & Uyeda, 1980;Pilkis et al, 1982), skeletal muscle (Riquelme et al, 1978a,b;Kemp et al, 1981) and kidney, brain and red cells (Mendicino et al, 1978;Marcus et al, 1979;Lagrange et al, 1980), but the effect ofphosphorylation on catalytic activity has been small and rather conflicting. One possible explanation for this might be partial proteolysis of the enzyme during the lengthy procedures used for purification.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Adipose-tissue phosphofructokinase. Rapid purification and regulation by phosphorylation in vitro

Sale¹,

Denton²

1985

Biochemical Journal

View full text Add to dashboard Cite

A new procedure for the purification of phosphofructokinase using Blue Dextran-Sepharose is described. This allowed an approx. 1000-fold purification of phosphofructokinase from rat white and brown adipose tissue to be achieved in essentially a single step. The purified enzymes from both tissues were found to exhibit hyperbolic kinetics with fructose 6-phosphate, to be inhibited by ATP and citrate, and to be activated by 5'-AMP, phosphate and fructose 2,6-bisphosphate. The enzymes were phosphorylated by the catalytic subunit of cyclic AMP-dependent protein kinase, and phosphorylation was found to be associated with increases in activity when the enzymes were assayed under appropriate sub-optimal conditions. In particular, the phosphorylated enzymes exhibited less inhibition by ATP and the white-adipose-tissue enzyme was more sensitive to activation by fructose 2,6-bisphosphate. It is suggested that an increase in the cytoplasmic concentration of cyclic AMP in tissues other than liver may result in an increase in glycolysis through the phosphorylation of phosphofructokinase by cyclic AMP-dependent protein kinase.

show abstract

Section: Discussioncontrasting

confidence: 81%

Section: Introductionmentioning

confidence: 99%

Adipose-tissue phosphofructokinase. Rapid purification and regulation by phosphorylation in vitro

Sale¹,

Denton²

1985

Biochemical Journal

View full text Add to dashboard Cite

show abstract

“…It has been shown previously that of other activators of phosphofructokinase, AMP activates phosphorylation but to a lesser extent and P¡, another activator of phosphofructokinase, has no effect on phosphorylation of phosphofructokinase (Kemp et al, 1981). It was also shown previously that citrate inhibits phosphofructokinase phosphorylation (Kemp et al, 1981). As shown in Table II, 1 mM citrate inhibits phosphofructokinase phosphorylation even in the presence of 200 µ fructose-1,6-P2…”

Section: Resultsmentioning

confidence: 53%

“…In the present study, as shown in Table II, the sugar bisphosphates fructose-2,6-P2, fructose-1,6-P2, dependent protein kinase to the same maximum extent. It has been shown previously that of other activators of phosphofructokinase, AMP activates phosphorylation but to a lesser extent and P¡, another activator of phosphofructokinase, has no effect on phosphorylation of phosphofructokinase (Kemp et al, 1981). It was also shown previously that citrate inhibits phosphofructokinase phosphorylation (Kemp et al, 1981).…”

Section: Resultsmentioning

confidence: 87%

“…Effect of Sugar Bisphosphates on Kinetics of Phosphorylation of Phosphofructokinase. It is known that the initial rate of phosphorylation of muscle (Kemp et al, 1981) and liver (Pilkis et al, 1982b) phosphofructokinase is increased by allosteric activators. In the present study, as shown in Table II, the sugar bisphosphates fructose-2,6-P2, fructose-1,6-P2, dependent protein kinase to the same maximum extent.…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Binding of hexose bisphosphates to muscle phosphofructokinase

Foe¹,

Latshaw²,

Kemp³

1983

Biochemistry

View full text Add to dashboard Cite

On the basis of kinetic activation assays, the apparent affinity of muscle phosphofructokinase for fructose 2,6-bisphosphate was about 9-fold greater than that for fructose 1,6-bisphosphate, which in turn was about 10 times higher than that for glucose 1,6-bisphosphate. Equilibrium binding experiments showed that both fructose bisphosphates bind to phosphofructokinase with negative cooperativity; the affinity for fructose 2,6-bisphosphate was about 1 order of magnitude greater than the affinity for fructose 1,6-bisphosphate. Binding of fructose 2,6-bisphosphate to phosphofructokinase was antagonized by fructose 1,6-bisphosphate and glucose 1,6-bisphosphate and vice versa. Both fructose bisphosphates promoted aggregation of the enzyme to higher polymers as indicated by sucrose density gradient centrifugation. Other indicators of phosphofructokinase conformation such as thiol reactivity and maximum activation of in vitro phosphorylation by the catalytic subunit of cyclic AMP-dependent protein kinase gave identical results in the presence of fructose 2,6-bisphosphate, fructose 1,6-bisphosphate, or glucose 1,6-bisphosphate, indicating a common conformation is produced by all three ligands. It is concluded that the sugar bisphosphates bind to a single site on the enzyme.

show abstract

Fructose 2,6‐Bisphosphate

Schaftingen

1987

Advances in Enzymology - And Related Areas of Molecular Biology

171

View full text Add to dashboard Cite

Studies on the phosphorylation of muscle phosphofructokinase.

Cited by 60 publications

References 26 publications

Adipose-tissue phosphofructokinase. Rapid purification and regulation by phosphorylation in vitro

Adipose-tissue phosphofructokinase. Rapid purification and regulation by phosphorylation in vitro

Binding of hexose bisphosphates to muscle phosphofructokinase

Fructose 2,6‐Bisphosphate

Contact Info

Product

Resources

About