SL MD4

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?
Need enzyme inhibitor
ACE - Angiotensin Converting Enzyme
angiotensin I ? angiotensin II
dipeptide
Inactive
Active causes high blood pressure
4
Following the lead
But proteins are digested in the stomach
Venom of Brazilian Arrowhead Viper can kill by
lowering blood pressure
It contained several proteins which were ACE
inhibitors
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(No Transcript)
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.
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(No Transcript)
9
After synthesising hundreds of compounds with
proline in
Not a protein so can be taken orally!
10
(No Transcript)
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