11: Amino Acid Metabolism Flashcards
What are the 3 main ways the body acquires amino acids?
dietary proteins, protein breakdown in body, and transamination
What molecules in brought in by every amino acid?
NH4+
What are some other compounds that amino acids contribute a N to?
GABA (neurotransmitter), norepinephrine/epinephrine, pyrimidines, purines
In nonessential amino acid reactions, ___ arrows are double-sided
some
What enzymes play a major role in amino acid reactions?
ATases
When does amino acid degradation occur more often?
when an AA is in abundance or when the animal is in negative nitrogen balance
What vitamin is usually required by ATases?
pyridoxal phosphate (Vit B6)
What is the results of ATase reactions?
a new AA and a new alpha keto acid
ALT
alanine amino transferase
Where is ALT predominantly found?
liver
AST
aspartate aminotransferase
Where is AST predominantly found?
liver, heart, skeletal muscle, kidneys, brain, RBCs
What does ALT convert?
alanine to glutamine
What molecule is the result of serine degradation?
3-phosphoglycerate
Why is synthesis and degradation of serine not reverse reactions?
different enzymes are used
In essential amino acid reactions, ___ arrows are double-sided
few
What 2 enzymes are commonly shared by branched chain AA metabolism?
aminotransferase and keto acid dehydrogenase
Maple syrup urine disease
aminals have a deficiency in branched chain keto acid dehydrogenase and excrete urine that smells like maple syrup due to the excess branched chain keto acids
What does a deficiency in PAH (phenylalanine hydroxylase) cause?
PKU (phenylketonuria)
PKU tratment
special diet (low phenylalanine)
What AA are cats deficient in?
taurine
What are some outcomes of tryptophan metabolism?
NAD synthesis, acetyl CoA synthesis, or excretion
What AA is the precursor for epinephrine?
tyrosine
TLI
trypsin like immunoreactivity; the inadequate secretion of pancreatic enzymes which is a sign of maldigestion
