Glycolysis Review

  1. What steps use ATP?
    • Glucose --> G6P (hexokinase)
    • F6P --> F-1,6,BP (PFK-1)
  2. What steps yield ATP?
    • 1,3,BPG --> 3-PG (phosphoglycerol kinase)
    • PEP --> Pyruvate (pyruvate kinase)
  3. What step yields NADH?
    GAP --> 1,3,BPG (GAP-DH)
  4. What are the regulatory steps?
    • Glucose --> G6P (hexokinase)
    • Fructose-6-P --> F-1,6-P (PFK-1)
    • PEP --> Pyruvate (pyruvate kinase)
  5. How is hexokinase regulated?
    (-) G6P
  6. How is PFK-1 regulated?
    • (-) ATP and citrate
    • (+) ADP, AMP and F-2,6,-biphosphate
  7. How is pyruvate kinase regulated?
    • (-) ATP, alanine
    • (+) F-1,6-BP
  8. What does biphosphoglycerate mutase do?
    • Coverts 1,3 BPG to 2,3 BPG
    • Converts 2,3 BPG to 3 PG
  9. What is the difference regarding Km and affinities for glucose between hexokinase and glucokinase:
    • Hexokinase: Low Km and high affinity for glucose
    • Glucokinase: High Km and low affinity for glucose
  10. Does hexokinase or glucokinase have a higher Vmax and what does that mean?
    Glucokinase has a higher Vmax and it means it will have a higher turnover rate from glucose to G6P to regulate glucose concentration in the blood.
  11. What is interesting about the brain isozyme of pyruvate kinase?
    It has no allosteric sites for regulation
  12. Explain glucagon effect on glycolysis?
    • Low Food - High Glucagon
    • High cAMP
    • High protein kinase A
    • Phosphorylated PFK-2
    • Low F-2,6-BPG
    • Low PFK-1
    • Low Glycolysis
  13. In what state is PFK-2 active?
    Dephosphorylated State
  14. Where does a pyruvate kinase deficiency manifest?
  15. What occurs in a pyruvate kinase deficiency and why?
    • Hemolytic anemia
    • Membrane transporters are not function and H2O enters the cell
  16. In times of low O2, what happens to the Pyruvates via what enzyme?
    • Converted to Lactate to recycle the NAD+
    • Lactate dehydrogenase
  17. What are the 3 fates of pyruvate?
    • Alanine
    • TCA
    • Oxaloacetate via Pyruvate Carboxylase
  18. What 2 enzymes exist as isozymes within glycolysis?
    • Hexokinase
    • Pyruvate Kinase
  19. What type of energy formation is utilized within tumors and why?
    • Glycolysis
    • Due to poor vasculature
Card Set
Glycolysis Review
Med School - Glycolysis