Topic 11: Amino Acid Anabolism Flashcards
What are the ESSENTIAL AAs?
PVT. TIM HALL
Phe, Val, Thr, Trp, Ile, Met, His, Arg, Leu, Lys
FVTWIMHRLK
Any Help In Learning These Little Molecules Proves Truly Valuable
What are the NON-essential AAs?
Ala, Asp, Asn, Cys, Glu, Gln, Gly, Pro, Ser, Tyr
How do we make Glu?
from a-KG via Glutamate-DH, transaminases, etc.
How do we make Gln?
from Glutamate via GLUTAMINE SYNTHETASE (implies we need ATP)
How do we make Ala?
from Pyruvate via ALT/SGPT
How do we make Asp?
from OAA via AST/SGOT
How do we make Asn?
from Asp via ASPARAGINE SYNTHETASE (implies we need ATP)
How do we make Tyr?
from Phe via PAH
How do we make Pro?
from Glutamine
Glu –> Glutamine semialdehyde becomes Glutamic semialdehyde by losing H+ then spontaneously delta-Pyrroline-5-carboxylate (ring closes) –> via Pyrroline-5-carboxylate Reductase is reduced to become the ringed PROLINE Amino Acid
How do we make Serine?
from 3-PhosphoGlycerate from step 6 glycolysis
3-phosphoglycerate (Step 6 Glycolysis) via 3-PGDH becomes 3-phosphopyruvate (generates NADH) –> AAtransferase takes amino from GLU to make 3-Phosphoserine –>
Phosphatase removes phosphate to make SERINE! (uses H2O in this step)
How do we make Glycine?
From SERINE in the presence of tetrahydrofolate and enzyme REMOVE h2O to make GLYCINE!!
How do we make Cysteine?
from METHIONINE and ATP (need Serine too)
Met + ATP –> Adomet –> Adenosylhomeocyteine –> Homocysteine + Serine –> link via Sulfur –> CYSTEINE takes sulfur and also get alpha-ketobutyrate
This is the normal breakdown pathway of Methionine
What are the CONDITIONALLY ESSENTIAL AAs?
Cysteine (Cys/C): Neonates
Tyrosine (Tyr/Y): PKU animals
Glutamine (Gln/N): growing infants and severe illness
Arginine (Arg/R): infants, children, severe illness
CYNR
What are the Carbon Sources for non-essentials?
Glucose makes:
Pyruvate –> Alanine
OAA–> Aspartate
alpha-ketoglutarate –> Glutamate
3-Phosphoglycerate –> Serine
What is Taurine used for?
Membrane stabilization
NeuroINHIBITORY transmitter
Primary Conjugate of BILE - especially in CATS
Is Taurine a sulfonic acid or carboxy acid?
Sulfonic Acid!
What vitamin does Taurine require?
B6/Pyridoxine
What is the issue with taurine and mostly-plant diets?
TAURINE DEFICIENT! must eat meat!!!!!
What are symptoms of TAURINE Deficiency?
Heart Failure! (Dilated Cardiomyopathy), Retinopathy, Renal Disease, Fat/Emulsification absorption (or lack there of), reproductive failure, immune deficiency
What is Glutamate capable of as a neurotransmitter?
STIMULATORY itself
can make GABA –> INHIBITORY
MSG–> chinese restaurant syndrome –> fidgity, head aches,
What is Glycine capable of as a neurotransmitter?
INHIBITORY in the spinal cord, blocking motor impulses,
What is Tyrosine capable of as a neurotransmitter?
It’s NOT, BUT it is the foundation for:
Dopamine: INHIBITORY voluntary movement, tremors –> PARKINSON’S
Norepinephrine: SNS –> heart rate, sweating, vasoconstriction
Epinephrine: glycogen metabolism, fight or flight, uses Methionine for methyl group
Should you be able to recognize Tyrosine structure?
YES HE SAID KNOW THE STRUCTURE
its AA with a phenyl ring and a hydroxy (OH) hangin off the ring
What hormone is Tyrosine important for?
THYROXINE!
