Part 2. Handling of Carbon Amino Skeletons

Question 1

How are the carbons skeletons of amino acids handled?

Answer 1

They are converted to molecules that can enter other metabolic pathways, either for fuel or as precursors of other molecules

Slide 6 Mar 15

Question 2

What are glycogenic vs ketogenic amino acids?

Answer 2

Amino acids that are catabolized to pyruvate or an intermediate of the TCA cycle are termed glucogenic (since they are used for glucose synthesis by gluconeogenesis)
Lysine and lucine
Slide 8-11 Mar 15

Amino acids that are catabolized to acetyl CoA or acetoacetate (a ketone body) are termed ketogenic (they cannot give rise to the net synthesis of glucose but rather lead to formation of fatty acids, ketone bodies, or their precursors)

Question 3

Memorize the catabolic pathway for Asn in mitochondria

Slide 12 Mar 15

Answer 3

Okay

Question 4

Memorize the catabolic pathway for phenylalanine

Slide 13 Mar 15

Answer 4

Okay

Question 5

What is phenylketonuria (PKU)?

Answer 5

Phenylalanine hydroxylase activity
Most common clinically encountered unborn error of amino acid metabolism
Increased [phenylalanine] in tissues, plasma and urine increased [phenyllactate, phenylacetate] makes musty smell in urine

Causes mental retardation, failure to all and talk, seizure, tremor, failure to grow, light skin and hair colour

Question 6

How are acyl-coa derivatives made from the catabolism of branched chain amino acids?

Answer 6

Slide 15 Mar 15

Branched-chain-α-keto acid dehydrogenase complex
^ if inhibited it causes maple syrup urine disease