1. SL MD4 Enzyme inhibitors as medicines

2. A bit like the antagonists! Noradrenaline (neurotransmitter) Fits into receptor site Electrical impulse sent to heart muscles Increases heart beat Bad for heart Antagonist (propanolol) blocks receptor site Angiotensin I (substrate) Fits into active site of enzyme (ACE) Changes it to angiotensin II Increases blood pressure Causes heart attacks and strokes ACE inhibitor (captopril) blocks active site

3. What causes the high blood pressure? angiotensin I  angiotensin II + dipeptide ACE - Angiotensin Converting Enzyme Inactive Active – causes high blood pressure Need enzyme inhibitor

4. Following the lead Venom of Brazilian Arrowhead Viper can kill by lowering blood pressure It contained several proteins which were ACE inhibitors But proteins are digested in the stomach

6. Try Ass 9.

7. Back to the lead compounds.. Active proteins from snake venom had the amino acid proline at the COOH end of the chain.

9. After synthesising hundreds of compounds with proline in … Not a protein so can be taken orally!

11. Try Ass 10.

12. A bit like the antagonists! Noradrenaline (neurotransmitter) Fits into receptor site Electrical impulse sent to heart muscles Increases heart beat Bad for heart Antagonist (propanolol) blocks receptor site Angiotensin I (substrate) Fits into active site of enzyme (ACE) Changes it to angiotensin II Increases blood pressure Causes heart attacks and strokes ACE inhibitor (captopril) blocks active site