1. CHMI 2227E Biochemistry I Enzymes: Regulation
CHMI E.R. Gauthier, Ph.D.

2. Regulation of enzyme activity
CHMI E.R. Gauthier, Ph.D.

3. Regulation of enzyme activity 1. Allostery
CHMI E.R. Gauthier, Ph.D.

4. Regulation of enzyme activity 1. Allostery
ATCase
Asp
Carbomoyl
phosphate
CHMI E.R. Gauthier, Ph.D.

5. Regulation of enzyme activity 1. Allostery - ATCase
CHMI E.R. Gauthier, Ph.D.

6. Regulation of enzyme activity 1. Allostery - ATCase
CTP
ATCase
CHMI E.R. Gauthier, Ph.D.

7. Regulation of enzyme activity 2. Regulatory subunits
ATP
cAMP
Adenylate
Cyclase
Phosphodiesterase
AMP
Caffeine
CHMI E.R. Gauthier, Ph.D.

8. Regulation of enzyme activity 3. Regulation by covalent modification
CHMI E.R. Gauthier, Ph.D.

9. Regulation of enzyme activity 3. Regulation by phosphorylation
CHMI E.R. Gauthier, Ph.D.

10. Regulation of enzyme activity 3. Phosphorylation  Adrenalineb g
G Protein
Adrenaline receptor
Adenylate cyclase
ATP
cAMP
Protein Kinase A
(inactive)
↑Intracellular glucose
PKA-cAMP
(active)
↑Energy
Run Like Hell!
Glycogen
(glucose stores)
Phosphorylase
kinase
Kinase-PO4
Phosphorylase-PO4
Inside the cell
Outside the cell
CHMI E.R. Gauthier, Ph.D.

11. Regulation of enzyme activity 4. Regulation of enzyme stability
CHMI E.R. Gauthier, Ph.D.

12. Regulation of enzyme activity 4. Regulation of enzyme stabilityUb E1 E2 E3
CHMI E.R. Gauthier, Ph.D.

13. Regulation of enzyme activity 4. Regulation of enzyme stabilityUb
Degraded
enzyme
Proteasome
CHMI E.R. Gauthier, Ph.D.

14. Regulation of enzyme activity 5. Limited proteolysis
CHMI E.R. Gauthier, Ph.D.

15. Regulation of enzyme activity 5. Limited proteolysis
CHMI E.R. Gauthier, Ph.D.

16. Regulation of enzyme activity 5. Limited proteolysis
Small intestine
Secreted by
pancreas
CHMI E.R. Gauthier, Ph.D.

17. Regulation of enzyme activity 5. Limited proteolysis
CHMI E.R. Gauthier, Ph.D.