Biosynthesis of Amino Acids

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Biosynthesis of Amino Acids

• M.Prasad Naidu
• MSc Medical Biochemistry, Ph.D,.

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Overview
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Overview (cont)
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Biosynthetic Families

• Metabolic Precursors Amino Acids
• a-ketoglutarate Glutamate
• Glutamine
• Proline
• Arginine
• 3-Phophoglycerate Serine
• Glycine
• Cysteine

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Biosynthetic Families (cont)

• Metabolic Precursors Amino Acids
• Oxaloacetate Aspartate, Asparagine
• Methionine, Threonine,
• Lysine
• Pyruvate Alanine, Valine, Leucine
• Isoleucine

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Biosynthetic Families (cont)

• Metabolic Precursors Amino Acids
• Phosphoenolpyruvate Tryptophan
• and erythrose 4-phosphate Phenlyalanine
• Tyrosine
• Ribose 5-phophate Histidine

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a-Ketoglutarate Family
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a-Ketoglutamate to glutamate/glutamine

• Glutamate NH4 ATP

Glutamine synthetase
Glutamine ADP Pi H
a-Ketoglutamate glutamine NADPH H
2 glutamate NADP
Glutamate synthase
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a-Ketoglutamate to glutamate/glutamine

• Net Reaction
• a-Ketoglutarate NH4 NADPH ATP
• L-glutamate NADP ADP Pi

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a-Ketoglutarate Family
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Synthesis of Proline
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Synthesis of Proline
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Synthesis of Arginine
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Synthesis of Arginine
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3-Phosphoglycerate Family
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Synthesis of Serine and Glycine
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Synthesis of Cysteine
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Oxoloacetate Family
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Synthesis of Aspartate and Asparagine
Aspartate
Oxaloacetate
Transamination from glutamate
Amidation with Glutamine donating NH4
Asparagine
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Synthesis of Lysine, Methionine, and Threonine

• See handout

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Pyruvate Family
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Synthesis of Alanine
Alanine
Pyruvate
Transamination from glutamate
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Synthesis of Isoleucine, Valine,and Leucine

• See handout

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Phosphoenolpyruvate and erythrose 4-phosphate
Family
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Synthesis of Chorismate
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Synthesis of Tryptophan
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Synthesis of Tyrosine and Phenylalanine
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Synthesis of Tyrosine and Phenylalanine (cont)
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Biosynthesis of Histidine

• See handout

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Possible Test Questions

1. Provide the 6 metabolic precursors and the amino
   acids which they lead to.
2. Duplicate the Amino Acid Synthesis Overview Flow
   Chart. Expand the sections need to show the
   synthesis of Glutamate, Glutamine, Proline,
   Arginine, Serine, Cysteine, Glycine, and starting
   from Chorismate Tryptophan, Tyrosine and
   Phenylalanine. (40 points!!)