Biosynthesis of Amino Acids

By

Prachee Rajput

Overview

Overview (cont)

Biosynthetic Families

Metabolic Precursors Amino Acidsα-ketoglutarate

GlutamateGlutamineProlineArginine

3-Phophoglycerate SerineGlycine

Cysteine

Biosynthetic Families (cont)

Metabolic Precursors Amino Acids

Oxaloacetate Aspartate, Asparagine

Methionine, Threonine,

Lysine

Pyruvate Alanine, Valine, Leucine

Isoleucine

Biosynthetic Families (cont)

Metabolic Precursors Amino Acids

Phosphoenolpyruvate Tryptophan

and erythrose 4-phosphate Phenlyalanine

Tyrosine

Ribose 5-phophate Histidine

α−Ketoglutarate Family

α−Ketoglutarate

Glutamate

Glutamine Proline Arginine

α-Ketoglutamate to glutamate/glutamine

Glutamate + NH4+ + ATP

Glutamine synthetase

Glutamine + ADP + Pi + H+

α-Ketoglutamate + glutamine + NADPH + H+

Glutamate synthase 2 glutamate + NADP+

α-Ketoglutamate to glutamate/glutamine

Net Reaction:

α-Ketoglutarate + NH4+ + NADPH + ATP

L-glutamate + NADP+ + ADP + Pi

α−Ketoglutarate Family

α−Ketoglutarate

Glutamate

Glutamine Proline Arginine

Synthesis of Proline

Synthesis of Arginine

Synthesis of Arginine

3-Phosphoglycerate Family

3-Phosphoglycerate

Serine

Glycine Cysteine

Synthesis of Serine and Glycine

Synthesis of Cysteine

Oxoloacetate Family

Oxaloacetate

Aspartate

Asparagine Methionine Lysine Threonine

Synthesis of Aspartate and Asparagine

Oxaloacetate AspartateTransamination from glutamate Amidation with

Glutamine donatingNH4

+

Asparagine

Synthesis of Lysine, Methionine, and Threonine

• See handout

Pyruvate Family

Pyruvate

Alanine Valine Leucine Isoleucine

Synthesis of Alanine

Pyruvate AlanineTransamination from glutamate

Synthesis of Isoleucine, Valine,and Leucine

• See handout

Phosphoenolpyruvate and erythrose 4-phosphate Family

Phosphoenolpyruvate +

erythrose 4-phosphate

Chorismate

Tryptophan Tyrosine Phenylalanine

Synthesis of Chorismate

Synthesis of Tryptophan

Synthesis of Tyrosine and Phenylalanine

Synthesis of Tyrosine and Phenylalanine (cont)

Biosynthesis of Histidine

• See handout

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!!)