b. What is the metabolic advantage of having the liver PK activated by fructose-1,6-bisphosphate? c. If the liver PK responded hyperbolically to PEP and were otherwise unregulated, how might gluconeogenesis be affected? 5. What reactions are used to circumvent the pyruvate kinase reaction in liver gluconeogenesis? 6. What reaction does phosphofructokinase-1 catalyze? 7. What reaction is used to circumvent PFK-1 in gluconeogenesis? 8. How does the small molecule fructose-2,6-bisphosphate alter the activities of PFK-1 and fructose-1,6-bisphosphatase?
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The liver pyruvate kinase (PK) is activated by fructose-1,6-bisphosphate (FBP) to ensure that glycolysis and gluconeogenesis do not occur simultaneously. This is because FBP is an intermediate of glycolysis, and its presence indicates that glycolysis is active. Show more…
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