Block 3 - AA Degradation and Special Products Flashcards
an amino acid whose carbons are converted to glucose are known as ________ amino acids
glucogenic
an amino acid whose carbons are converted to acetyl CoA or acetoacetate are known as ________ amino acids
ketogenic acids
is tyrosine glucogenic or ketogenic?
both
what are the 2 AA’s that are exclusively ketogenic?
lysine and leucine
are non-essential AA’s glucogenic or ketogenic?
glucogenic
succinyl CoA, oxaloacetate, fumurate, and pyruvate are all major gloconeogenic or ketoneogenic substrates?
gluconeogenic substrates
is acetoacetate and acetyl-CoA a major gluconeogenic substrate?
no, both are major ketogenic substrates
what are the 3 amino acids that are part of the pyruvate pathway, and can be directly convert to pyruvate?
cysteine, alanine, and serine
what 2 AA’s are indirectly a factor in the pyruvate pathway? what direct AA does it help to form?
threonine is converted to glycine, then glycine to serine, which is then converted to pyruvate
deficiency in the ______ _____ _____ leads to nonketotic hyperglycinema
glycine cleavage complex (GCC)
how many pathways are there for serine to for pyruvate?
2
what 2 AA’s can be considred interchangeable in the pyruvate pathway?
glycine and serine
choline and ethanolamine are derived from ______
serine
PLP
Pyridoxal phosphate, the active form of vitamin B₆,
of the pathways for serine to form pyruvate, the major factor involved in them are _______ _______ in the first, single step, and ______ and ________ used in the other
serine dehydratase, and PLP and 3-phosphoglycerate (3-PG)
amino acids that are converted to acetyl Co-A are considered to be _______
ketogenic
tyrosine, a conditionally essential AA, is produced from _____
phenylalanine
is the synthesis of tyrosine reversible?
no
is tyrosine glucogenic or ketogenic?
both
oxidation of tyrosine forms what two products?
acetoacetate (ketogenic)and fumurate (glucogenic)
Deficiencies in different enzymes of the pathway from phenylalanine to form tyrosine to be oxidized to acetoacetate and fumurate can result in what 3 diseases?
phenylketonuria (PKU), tyrosinemia, and alcaptonuria
a defect or deficiency in the conversion of phenylalanine to tyrosine results in what conition?
PKU - phenylketonuria
PKU causes accumulation of ________
phenylpyruvate
is tryptophan glucogenic or ketogenic?
both
the oxidation of tryptophan forms what 4 major things?
alanine, acetyl CoA, formate, and NAD(P)
Deficiency in α-ketoacid decarboxylase leads to ______________
Maple syrup urine disease (MSUD)
if an AA yields acetyl CoA is it keto- or glucogenic?
ketogenic
Valine yields _______
propionyl-CoA
Isoleucine yields ________ and __________
acetyl-CoA and propionyl-CoA
Leucine yields ________ and __________
acetyl-CoA and acetoacetate
deficiencies in what three AA’s can result in maple syrup urine disease?
valine, isoleucine, and leucine
AAs degraded to form succinyl CoA can/cannot be synthesized in humans
cannot
what AA’s are degraded to form succinyl CoA?
methionine, threonine, valine, and isoleucine (Val and Iso b/c proprionyl CoA is converted to Succinyl CoA)
Propionyl CoA is carboxylated in a biotin-requiring reaction, forming ___________, which is then rearranged in a vitamin B12-requiring reaction, producing succinyl CoA
methylmalonyl CoA
Methylmalonyl CoA is rearranged to succinyl CoA in a reaction requiring what vitamin?
vitamin B12
in the catabolism of branched AA’s the first step is when the AA is converted to ________ by a __________reaction
alpha-ketoacid by transamination
in the catabolism of branched AA’s the second step is catalyzed by __________
alpha-ketoacid dehydrogenase (or decarboxylase)
Histidine, Arginine, Glutamate, Glutamine, and Proline can all be broken down into what?
glutamate 5-semialdehyde
Carbons of fumarate are derived from _______
aspartate
The major route for the disposal of Asp involves conversion to ________ via transamination, but can form _______ in the urea cycle
OAA, fumurate
The first integrase inhibitor-based single tablet regimen use to treat HIV-1 is _________
Stribild
