Synthesis of fats

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Lecture 15 Synthesis of fats
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• Biosynthetic reactions.
• You do not need to know anything about the
• synthesis or steroids, unsaturated fatty
  acids etc.

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• Synthesis of Fatty Acids
• Occurs in the cytoplasm
• Requires NADPH
• Uses an acyl carrier protein
• Begins at the CH3CH2- end

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• General Plan
• Preparation of acetyl-CoA
• Preparation of malonyl-CoA
• Reactions proper.

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(1) Preparation of acetyl-CoA
ACP acyl carrier protein points it to the
biosynthetic path.
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Synthase
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Preparation for fatty acid biosynthesis
(2) Synthesis of malonyl-CoA
AcetylCoA
2C
3C
MalonylCoA
Acetyl-CoA carboxylase Requires ATP and biotin.
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(2b) synthesis rather than CoA to distinguish
synthesis from degradation.
MalonylACP
ACP acyl carrier protein.
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• Step 3 condensation reaction start of the
  synthesis proper

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• Step 4 the first reduction

OH O H
CH3-C- CH2- CS-ACP NADP
Hydroxylbutyryl-ACP
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• Step 5 dehydration

OH O H
CH3-C- CH2- CS-ACP NADP
Hydroxylbutyryl-ACP
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Step 6 the second reduction
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Synthesis of Fatty Acids

• The cycle now repeats on butyryl-ACP

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Very important