enzymes as drug targets

What are enzymes?

Biological catalysts that speed up biochemical reactions by lowering the activation energy without being consumed in the process

What are the key properties of enzymes?

• Specificity: Specific to their substrates and reactions.

• Active Site: Region where substrate binding and catalysis occur.

• Regulation: Modulated by activators, inhibitors, or covalent modifications.

• Reusability: Remain unchanged after catalysis and can be reused

What is the Michaelis-Menten equation?

v = (vmax [S])/(Km + [S])

V max

Maximum rate of reaction

Km

Substrate concentration at 1/2 Vmax

What are the types of enzyme inhibition?

• Competitive: Inhibitor competes with the substrate for active site binding. Vmax =, Km is lower

• Non-competitive: Inhibitor binds elsewhere, reducing enzyme activity. Vmax is lower, Km =

How do HIV protease inhibitors work?

inhibit HIV protease, preventing viral polyprotein processing and maturation.

• Drugs: Ritonavir, lopinavir.

What is the target of penicillin and similar antibiotics?

Binds irreversibly to DD transpeptidase which carries out the crosslinking to peptidoglycan, disrupting bacterial cell wall integrity.

What is the target of NSAIDs like aspirin and ibuprofen?

Cyclooxygenase (COX) enzymes, which are involved in prostaglandin synthesis.

• Mechanism: Inhibit prostaglandin production, reducing pain and inflammation

How do ACE inhibitors work?

Inhibit angiotensin-converting enzyme (ACE), lowering blood pressure by reducing angiotensin II levels.

• drugs: Enalapril, lisinopril