1. After Digestion And Absorption
Of Food What Next?

2. General Overview Of Metabolism (Carbohydrate, Protein, Fat)

3. Carbohydrate Chemistry and Metabolism
By Gladys Kaba

4. Outline Carbohydrate chemistry
Summary of digestion and absorption of carbohydrates.
General overview of metabolism

5. Outline 4. Carbohydrate Metabolism Glycolysis TCA cycle
Gluconeogenesis
Metabolism of (Fructose, galactose, Mannose)
PPP
Glycogenesis and Glycogenolysis

6. After Digestion And Absorption Of Carbohydrates What Next?
Carbohydrate Metabolism
(Glucose)

7. We eat food containing carbohydrates

8. General Overview Of Metabolism (Carbohydrate, Protein, Fat)

9. Overview Of Carbohydrate Metabolism

10. (1) Glycolysis - Summary
glycolysis occurs in the cytosol
Glucose (6C)
2 ATP
4 ADP
2 ADP
4 ATP
Location Of Glycolytic Enzymes?
2 NAD
2 NADH + H
2 Pyruvate (3C)

11. Functions/Importance Of Glycolysis
Glycolysis Provides Energy
Glycolysis Provides Substrate for Oxidation
Intermediates Products are used in Other Pathways
2,3-bisphosphoglycerate,
fatty acid and cholesterol synthesis
Alanine,
glycerol 3-phosphate

12. Cells With Special Needs Of Glycolysis
Erythrocytes (Red blood cells)
Lens and cornea of the eye
Cells in brain cells

13. Physiological And Pathophysiological Conditions with special need for Glycolysis
Fed State
Exercising muscles
Cancer cells-----Warburg effect

14. Phosphofructokinase-1
Fructose 6-phosphate
Glucose
Glucose 6-phosphate
Phosphohexose
isomerase
Hexokinase
Phosphofructokinase-1
Fructose 1,6-
bisphosphate
Pyruvate
kinase
Phosphoenolpyruvate
Pyruvate
2-Phosphoglycerate
Phosphoglycerate
mutase
Glyceraldehyde 3-phosphate dehydrogenase
1,3-Bisphosphoglycerate
Phosphoglycerate kinase
3-Phosphoglycerate

15. Glycolysis Regulation

16. Abnormalities Associated with Glycolytic pathway
Affected Glycolytic enzyme/reaction
Genetic Deficiencies
of Glycolysis
pyruvate kinase
phosphoglycerate kinase

17. Toxin affecting Glycolytic pathway
Mercury
Arsenic

18. After Glycolysis What next after?
Lactate (anaerobic)
Glucose → 2 Pyruvate
Acetyl-CoA (TCA cycle)

19. 1. Conversion of pyruvate to Acetyl CoA aerobic conditions
Location Of Pyruvate Dehydrogenase ?

20. Glycolysis cytoplasm Glucose Pyruvic acid Acetyl-CoA mitochondrion
Kreb’s Cycle
Glucose
Glycolysis
cytoplasm
Pyruvic acid
Acetyl-CoA
mitochondrion
Citric
Acid
Cycle
Electron Transport
ATP Production

21. Carbohydrate, protein, and Fat Metabolism

22. Kreb’s Cycle
Aka
Tricarboxylic Acid Cycle
TCA Cycle
Citric Acid Cycle
Location Of Pyruvate Dehydrogenase
And The TCA-cycle Enzymes?

24. Main Function of the Kreb’s cycle
Oxidative process
3 NADH
FADH2
GTP
X 2 per glucose
6 NADH
2 FADH2
2 GTP
All ultimately turned into ATP (oxidative phosphorylation/ electron transport chain)

27. Total Energy per glucose
A) Cytosol
Glycolysis
2 NADH
2 ATP
B) Mitochondrion
Pyruvate dehydrogenase
--Krebs
6 NADH
2 FADH2
2 GTP

28. Abnormalities / Diseases Associated With PDH And The TCA Cycle
Genetic Deficiency of Pyruvate Dehydrogenase
2) Genetic Diseases of the TCA Cycle :
Fumarase deficiency
Succinate dehydrogenase
α-ketoglutarate dehydrogenase

29. Abnormalities / Diseases Associated With PDH And The TCA Cycle
3) Thiamine Deficiency -- classical beriberi,
Pyuvate Dehydrogenase
α-ketoglutarate Dehydrogenase

30. Regulation of the Tricarboxylic Acid Cycle?
About half page to be submitted next Wednesday before The class.
Students Review Question?
Additional questions would be sent through the on Thursday.

31. After Glycolysis What next after?
Lactate (anaerobic)
Glucose → 2 Pyruvate
Acetyl-CoA (TCA cycle)

32. (Anaerobic conditions)
2. Conversion To Lactate
(Anaerobic conditions)
(oxidized)
(reduced)

34. Cori cycle Lactate can be transported by blood
Exercising muscles
and the Cori Cycle
Lactate can be transported by blood
to liver and used in gluconeogenesis

35. How do cytosolic/cytoplasmic NADH get into the mitochondrial?

36. How do cytosolic/cytoplasmic NADH get into the mitochondrial?
glycerol 3-phosphateshuttle - NADH as FADH
malate-aspartate shuttle- NADH as NADH

37. The malate-aspartate shuttle.

38. Overview Of Carbohydrate Metabolism

39. Gluconeogenesis
non-carbohydrate precursors are converted to glucose.

40. Gluconeogenesis Is Active
Tissues In Which
Gluconeogenesis Is Active
liver
Renal Cortex

41. Functions and importance
Gluconeogenesis
Maintaining the blood glucose in the fasted state
But the brain, red blood cells, and renal medulla, rely on glycolysis for ATP.

42. Physiological Conditions In Which Gluconeogenesis Is Especially Active
fasted state,
when stored as glycogen is depleted
plasma concentration of glucose decline

43. Physiological Conditions In Which Gluconeogenesis Is Especially Active
During prolonged physical exercise.
important in the neonate.
(the first few hours after delivery).

44. Gluconeogenesis starting material lactate, pyruvate, Oxaloacetate
glycerol
Some amino acids
propionic acid ( oxidation of odd-chain fatty acids and branched methyl fatty acids)

45. Biochemical Reactions Of Gluconeogenesis
Most are the same as glycolysis,
But in the opposite direction,
With some few exceptions

46. Phosphofructokinase-1
Fructose 6-phosphate
Glucose
Glucose 6-phosphate
Phosphohexose
isomerase
Hexokinase
Phosphofructokinase-1
Fructose 1,6-
bisphosphate
Pyruvate
kinase
Phosphoenolpyruvate
Pyruvate
2-Phosphoglycerate
Phosphoglycerate
mutase
Glyceraldehyde 3-phosphate dehydrogenase
1,3-Bisphosphoglycerate
Phosphoglycerate kinase
3-Phosphoglycerate

47. Three Physiologically Irreversible Steps Glycolysis And Gluconeogenesis Are Different
Glucokinase/Hesosekinase ---glucose 6-phosphatase
phosphofructokinase- 1 --fructose 1,6-bisphosphatase,

48. Three Physiologically Irreversible Steps Glycolysis And Gluconeogenesis Are Different
3. pyruvate kinase
A) Pyruvate carboxylase
B) Phosphoenolpyruvate carboxykinase

51. Localization of Gluconeogenesis
Most Of The Enzymes Are Found In The Cytosol, But
Pyruvate Carboxylase----- Mitochondria
Glucose 6-phosphatase------
Lumen Of The Endoplasmic Reticulum

54. Regulation of gluconeogenesis

55. General Overview Of Metabolism (Carbohydrate, Protein, Fat)