Amino Acid Oxidation Flashcards
What are the two major categories of amino group carbon skeletons?
Glucogenic
Ketogenic
What does it mean to be glucogenic?
TCA Cycle intermediates that can be shunted to gluconeogenesis
What does it mean to be ketogenic?
AcetylCoA derivatives that can be used for ketone body synthesis
Can we make glucose from proteins?
Yes, fairly easily
What does breakdown of Methionine synthesize?
Cysteine
What does the breakdown of Phenylalanine synthesize?
Tyrosine
What 4 glucogenic amino acids can form pyruvate?
Ala
Ser
Cys
Trp
What 2 glucogenic aa’s can form Oxaloacetate?
Asn
Asp
How many carbons are in amino acids that form pyruvate?
3 Carbons form the alpha-keto acid pyruvate
How many carbons are in amino acids that form oxaloacetate?
4 Carbons form the alpha-keto acid oxaloacetate
What 5 glucogenic amino acids can form alpha-KG?
Gln Pro Arg His Glu
How many carbons are in amino acids that form alpha-KG?
5 Carbons form alpha-KG but they are first funneled to Glu
What kind of glucogenic/ketogenic aa’s can form SuccinylCoA and AcetylCoA?
Branched Chain Amino Acids
What are the branched chain amino acids?
Ile
Val
Leu
What does Val form when oxidized?
PropionylCoA
Strictly glucogenic
What does Ile form when oxidized?
PropionylCoA and AcetylCoA
Both glucogenic and ketogenic
What does Leu form when oxidized?
Acetoacetate and AcetylCoA
Strictly ketogenic
Where does transamination of branched chain aa’s occur?
In muscle, kidney and brain
NOT THE LIVER
Which steps of oxidation do the branched chain amino acids share?
The first 2 steps
Separate after dehydrogenase complex
What two glucogenic aa’s can form SuccinylCoA exclusively?
Met
Thr
What do Met and Thr yield before being converted to propionylCoA?
alpha-ketoburyate
What is the byproduct of SuccinylCoA conversion from alpha-ketobutyrate?
Cysteine
What is PropionylCoA converted too?
SuccinylCoA
What two major cofactors are used when converting PropionylCoA to SuccinylCoA?
Biotin (Vit. B7)
Cobalamin