The inhibition of PFK-1 by ATP diminishes when the ADP concentration is high, as shown in the graph.What explains this observation?ADP levels regulate the association of the individual PFK-1 monomers.The [ATP]/[ADP] ratio regulates PFK-1 activity.ADP outcompetes ATP as a phosphoryl donor for PFK-1 at high concentrations.Binding of ADP to the catalytic site increases PFK-1 activity. The graph shows the effect of ATP on the allosteric enzyme phosphofructokinase-1 (PFK-1).PFK-1 activity (% of Vmax)100806040200Low[ADP][ATP]High[ADP]For a given concentration of fructose 6-phosphate, the PFK-1 activity increases with increasing concentrations of ATP, but thereis a point beyond which increasing the concentration of ATP inhibits the enzyme.

PFk-1 is an enzyme involved in glycolysis. It catalyzes the conversion of fructise-6-phoaphate to…

Answered: The inhibition of PFK-1 by ATP…

Biochemistry

6th Edition

ISBN:9781305577206

Author:Reginald H. Garrett, Charles M. Grisham

Publisher:Reginald H. Garrett, Charles M. Grisham

Chapter18: Glycolysis

Section: Chapter Questions

Problem 21P

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Which of these molecules has a higher phosphoryl potential than ATP? a) glucose-6-phosphate b) glucose-1-phosphate c) phosphoenolpyruvate d) glyceraldehyde-3-phosphate The most commonly used biochemical reducing agent is: a) NADH b) NADPH c) FADH2 d) LiALH4 Hexokinase catalyzes: a) conversion of glucose to glucose-6-phosphate b) conversion of glucose-6-phosphate to fructose-6-phosphate c) conversion of fructose-6-phosphate to fructose-1,6-biphosphate d) cleavage of fructose-1,6-biphosphate to glyceraldehyde-3-phosphate and dihydroxyacetone phosphate Which one of these molecules is not found in glycolysis? a) 1,3-biphosphoglycerate b) phosphoenolpyruvate c) pyruvate d) oxaloacetate The major regulatory enzyme of glycolysis is: a) hexokinase b) phosphofructokinase c) aldolase d) triose isomerase NADH is produced at which step in glycolysis? a) conversion of fructose-6-phosphate to fructose-1,6-biphosphate b) cleavage of fructose-1,6-biphosphate…
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The most commonly used biochemical reducing agent is: a) NADH b) NADPH c) FADH2 d) LiALH4 Hexokinase catalyzes: a) conversion of glucose to glucose-6-phosphate b) conversion of glucose-6-phosphate to fructose-6-phosphate c) conversion of fructose-6-phosphate to fructose-1,6-biphosphate d) cleavage of fructose-1,6-biphosphate to glyceraldehyde-3-phosphate and dihydroxyacetone phosphate Which one of these molecules is not found in glycolysis? a) 1,3-biphosphoglycerate b) phosphoenolpyruvate c) pyruvate d) oxaloacetate The major regulatory enzyme of glycolysis is: a) hexokinase b) phosphofructokinase c) aldolase d) triose isomerase NADH is produced at which step in glycolysis? a) conversion of fructose-6-phosphate to fructose-1,6-biphosphate b) cleavage of fructose-1,6-biphosphate to glyceraldehyde-3-phosphate and dihydroxyacetone phosphate c) conversion of glyceraldehyde-3-phosphate to 1,3-biphosphoglycerate d) conversion of phosphoenolpyruvate to…

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