Protein and Amino Acid Metabolism Supplement Flashcards
What amino acids come from 3-Phosphoglycerate?
Serine –> cysteine, glycine
What amino acids come from Glucose 6-Phosphate?
Histidine, but only a small amount from gut bacteria, considered an essential AA.
What AA comes from pyruvate?
alanine
What AA’s come from oxaloacetate and also go back into it for degradation?
asparagine and aspartate
What amino acids come from alpha keoglutarate?
glutamate –> glutamine and proline
What does the degradation of ketogenic AA produce?
Acetyl CoA
What does the degradation of glucogenic AA produce?
pyruvate or other intermediates of the TCA cycle
What AAs enter the TCA through fumarate?
Phe and Tyr
What AAs enter the TCA through Succinyl CoA?
Ile, Val, Met, Thr
What AAs enter the TCA through alpha ketoglutarate
gln, his, arg, pro (almost all w/ N grp) through glutamate
PHAG
what enzyme catalyzes the reaction of methionine to homosysteine?
homocysteine methyl transferase
what enzyme catalyzes the rxn of homocysteine to cystathionine?
What cofactor is required? What vitamin is it derived from?
cystothionine synthase Pyridoxal phosphate (PLP); comes from vitamin B6
degradation of what amino acid is screwed up in the diseases hyperhomocysteinemia and homocystinuria?
methionine( –> homocysteine –> cystathionone –> alpha ketobutyrate)
what organ systems are most affected from hyperhomocysteinemia and homocystinuria?
eye
skeletal
cns
vascular
What amino acids can’t be broken down in maple syrup urine disease?
branched chain amino acids
what enzyme is used to break down Val, Ile, and Leu?
What disease results from deficient activity of this enzyme?
BCKD
MSUD
In the brain, what amino acids are used to remove ammonia?
glu and gln
alpha keto glutarate –>glu –>gln –to liver–>gln –>glu and ammonia goes to urea cycle
In muscle, what amino acids are used to remove excess ammonia?
What enzymes are essential to do this?
alanine and glutamate
ALT changes pyruvate to ala w/ a nh3 and then turns it back to pyruvate in liver
GLDH removes NH4 in liver and puts it in urea cycle
What amino acids is creatine made from?
Met, Arg, Gly
MAGazINE
What enzyme changes creatine to phosphocreatine and generates ATP?
creatine kinase
Alkaptonuria is caused by a deficiency in what enzyme?
homogentistic acid oxidase (tyrosine –> homogentisate in the breakdown of phenylalanine)
What is the breakdown path of Phenylalanine?
Phe –> Tyr –> Homogentisate –>–> fumarate
PKU is due to what?
Deficiency in phenylalanine hydroxylase
In PKU, what molecules accumulate?
phenylactate and phenylacetate
What is the order of the urea cycle
NH4+ –> carbamoyl Pi –> citrulline –into mito –>citrulline –> argino succinate –> arginine –H20 comes in and Urea comes out –> ornithine
(OCAA)
What does ornithine transcarbomoylase do?
Carbamoyl Pi + ornithine –> citrulline
Urea cycle
What does arginosuccinate synthase do?
citrulline –> arginosuccinate
Urea cycle
What does Arginosuccinate lyase do?
Arginosuccinate –> arginine
Urea cycle
What does arginase do?
Arginine –> ornithine
Where water goes in and urea goes out!
Urea cycle
What are the common derivatives of tyrosine?
Dopamine –> norepinephrine –> epinephrine
thyroid hormone
melanin
What are derivatives of Tryptophan you should know?
Niacin –> nadh
serotonin –> melatonin
What derivative of Serine should you know?
Acetylcholine
What derivative of glutamate should you know?
GABA
