amino acid 2

4. Metabolic classification of amino acids:
according to metabolic fate or degradation products of amino acids
they may be:
Metabolic breakdown of amino acids
• Glucogenic amino acids-carbo n skeletons are broken down to pyruvate, a-ketoglutarate, succinyl-CoA, fumarate, or oxaloacetate (glucose precursors).
- TCA cycle intermediates or precursors to be metabolized to CO2, H2O, or for use in gluconeogenesis.
• Ketogenic amino acids, are broken down to acetyl-CoA, beta hydroxy butyrate or acetoacetate and therefore can be converted to fatty acids
Both glucogenic and ketogenic amino acids Yield ? -ketoglutarate, pyruvate, oxaloacetate, fumarate, or succinyl-CoA in addition to acetyl CoA or acetoacetate Isoleucine ,Threonine,Tryptophan ,Phenylalanine
Tyrosine
Amino acid metabolism and central metabolic pathways
Biomedical importance of amino acids
• The amino acids fulfill vario us functions in the living organism: For examples: Only the 20 proteinogenic amino acids are included in the genetic code and therefore regularly found in proteins. The genetic code is the set of rules by which information encoded within genetic material (DNA or mRNA sequences) is translated into proteins by living cells. DNA serves as the genetic blueprint of a cell
• Amino acids or their derivatives are also form components of lipidse. g., serine in phospholipids (cell membrane). The amino acid serine , which has a hydroxyl group side chain provides the head group for the negative
phospholipid, phosphatidyl serine. .

• Several amino acids function as neurotransmitters themselves such as glycine and glutamic acid, while others are precursors of neurotransmitters, mediators.