Amino Acid Metabolism Flashcards
Amino Acids
small organic compounds with an amino and carbohydrate terminus
Essential Amino Acids
mammals can’t make but need must get from diet
His, Ile, Leu, Lys, Met, Phe, Thr, Trp, Val
Nonessential Amino Acids
mammals can make
Ala, Asp, Asn, Glu, Ser
Conditionally Essential
can make most of what need
may require during illness/certain growth stages
Arg, Cys, Gln, Gly, Pro Tyr
What are the 20 amino acids used in?
Protein synthesis
What are the excitatory amino acids?
Glutamate and Aspartate
What are the inhibitory amino acids?
Glycine and GABA
How any amino acids can bacteria and plants make? What about mammals?
bacteria and plants make all 20
mammals can make about half
What is glutamate formed from?
alpha-ketoglutarate
Which two reactions does glutamine synthetase facilitate?
Phosphorylation and amination
What is glutamine important for?
removable of excess nitrogen
donates nitrogen into other biosynthetic pathways
How can mammals interconvert Pro and Arg?
the urea cycle and ornithine aminotransferase
How can bacteria make Pro and Arg?
directly from glutamate
What is Ser formed from?
3-phosphoglycerate from glycolysis
gets oxidized into 3-phosphohydroxypyruvate
a transamination forms phosphoserine
the phosphate is cleaved
The amination of pyruvate forms?
Alanine
The amination of oxaloacetate forms?
Aspartate
The amination of aspartate forms?
Asparagine
What helps in treatment of childhood acute lymphoblastic leukemia, acute, myeloid leukemia, and non-hodgkins lymphoma?
Asparaginase
What do malignant lymphocytes all require?
Serum Asn
Treatment of patients with Asparaginase in combo with other chemotherapy results in about what percentage of remission rates?
95%
What amino acids are derived from shikimate found in bacteria and plants?
aromatic amino acids
What two pathways does aromatic acid formation use?
glycolysis and pentose phosphate pathway
What is Histidine’s pathway similar to?
purine biosynthesis
What is histidine being studied as a drug target for?
tuberculosis, no approved drugs yet
What does GABA come from?
Glu
What does serotonin come from?
Trp
What does dopamine come from?
Phe or Tyr
What does Epinephrine/norepinephrine come from
Phe or Tyr
What does histamine come from?
His
What are the 3 possible states of amino acid degradation?
normal synthesis and degredation
diet high in protein
starvation/uncontrolled diabetes
Amino acid degradation converts amino acids to?
alpha-ketoacids first
then CO2 or water OR taken into gluconeogenesis to make glucose
Amino acid degradation process
lose nitrogen first
nitrogen enters the urea cycle/ is used in other pathways
carbon skeleton goes to the citric acid cycle to get broken down
breakdown products can be totally oxidized or used as intermediates
How much energy (percentage) comes from the amino acid degradation in the citric acid cycle?
10%
Acetyl Coa converts to acetoacetyl-CoA which breaks down what?
ketone bodies
Strictly ketogenic amino acids
Leu and Lys
Mixed Amino Acids
Phe
Tyr
Trp
Ile
Thr
Strictly Gluconeogenic
Asp and Asn
Glu, Gln, Arg, His, Pro
Met and Val
Ala, Cys, Gly, Ser