Nucleotide Metabolism | Myokinase & the Purine Nucleotide Cycle

The video explains the muscle purine nucleotide cycle, focusing on how it helps maintain ATP levels during exercise. It covers the role of adenylate kinase, AMP deaminase, and the IMP pathway in regulating AMP levels. The video also discusses the equilibrium shifts that occur to sustain ATP production, ensuring continued energy supply for muscle activity.

What is the primary role of AMPK in muscle cells during exercise?

• To increase AMP levels

• To convert ADP to ATP

• To signal for more catabolic reactions

• To inhibit ATP production

What is the main function of the purine nucleotide cycle in muscles?

• To inhibit oxidative phosphorylation

• To convert ATP to ADP

• To decrease AMP levels during exercise

• To increase ATP levels indefinitely

Which enzyme is responsible for converting AMP to IMP in the purine nucleotide cycle?

• Adenylate kinase

• AMP deaminase

• Adenylate succinate synthetase

• Inosine monophosphate dehydrogenase

Why does the purine nucleotide cycle waste a GTP molecule?

• To produce more AMP

• To convert IMP to inosine

• To inhibit ATP production

• To regulate AMP levels

What happens to IMP when adenylate succinate synthetase is inhibited?

• It inhibits AMPK

• It is converted back to AMP

• It is degraded into inosine

• It accumulates in the cell

How does the purine nucleotide cycle help maintain ATP levels during exercise?

• By increasing AMP levels

• By shifting equilibrium to produce more ATP

• By converting ATP to ADP

• By inhibiting glycolysis

What is the effect of decreasing AMP levels on the equilibrium of the adenylate kinase reaction?

• Shifts equilibrium to the right

• Shifts equilibrium to the left

• Increases ADP concentration

• Decreases ATP production