1. 1 SURVEY OF BIOCHEMISTRY Glycolysis

2. 2 Announcements Exam #2 on June 26 –Chapters 7, 8, 11, 12, 14 Bring calculators Study Session with Vonda –Thursday, June 26; 2-3:45 pm –Boggs 228

3. 3 Introduction to Glycolysis Glycolysis: breakdown of sugars Primary start point = glucose 10 enzymatic reactions

4. 4 Overview Stage I of Glycolysis 2 ATP’s invested 1 Glucose is broken into 2 phosphorylated molecules

5. 5 Overview Stage II of Glycolysis 4 ATP’s recovered 2 NADH’s produced GAP is converted to pyruvate

6. 6 Enzymes in Glycolysis Stage I: Energy Investment 1.Hexokinase Uses ATP 2.Phosphoglucose Isomerase [PGI] 3.Phosphofructokinase [PFK] Uses ATP 4.Aldolase Splits 6C into two 3C molecules 5.Triose Phosphate Isomerase [TIM]

7. 7 Enzymes in Glycolysis Stage II: Energy Recovery 6.Glyceraldehyde 3-Phosphate Dehydrogenase Uses NAD + to form NADH 7.Phosphoglycerate Kinase [PGK] Forms ATP (2 molecules) 8.Phosphoglycerate Mutase [PGM] 9.Enolase Forms high energy molecule 10.Pyruvate Kinase [PK] Forms ATP (2 molecules) Classify these on board

8. 8 Key Mechanisms Kinases: Transfer PO 3 2- to substrate Phosphoglucose Isomerase Aldolase GAP Dehydrogenase Phosphoglycerate Mutase

9. 9 Example of Kinase Activity Step 1: Hexokinase

10. 10 Phosphoglucose Isomerase Reaction Mechanism Step 2

11. 11 PGI Reaction Mechanism Base Catalysis

12. 12 PGI Reaction Mechanism Acid Catalysis

13. 13 PGI Reaction Mechanism H+H+ Base catalyzes ring closure

14. 14 Glyceraldehyde 3-Phosphate Dehydrogenase Step 6 Remember: Glycolysis produces 2 molecules of GAP, and therefore 2 molecules of NADH

15. 15 GAP Dehydrogenase Mechanism Free Enzyme

16. 16 GAP Dehydrogenase Mechanism Thiol Addition

17. 17 GAP Dehydrogenase Mechanism Dehydrogenation

18. 18 GAP Dehydrogenase Mechanism Phosphate Binding PiPi

19. 19 GAP Dehydrogenase Mechanism

20. 20 Phosphoglycerate Mutase

21. 21 Phosphoglycerate Mutase Mechanism

22. 22 Pyruvate Kinase

23. 23 What happens to pyruvate?

24. 24 PRS What is the maximum number of O 2 molecules that hemoglobin can bind? 1.One 2.Two 3.Three 4.Four

25. 25 PRS B cells mature in the ________. 1.Thymus 2.Bone marrow 3.Muscle tissue 4.Myosin

26. 26 PRS Oxygen binding to myoglobin results in what shaped curve? 1.Sigmoidal 2.Hyperbolic 3.Linear 4.Sinusoidal

27. 27 PRS Which of the following amino acids is not in the catalytic triad of serine proteases? 1.Ser 2.Thr 3.His 4.Asp

28. 28 PRS What is K m ? 1.The catalytic efficiency 2.The catalytic rate constant 3.1/2 V max 4.[S] at 1/2 V max