Amino Acid Catabolism

Question 1

NH3+ group can be

Answer 1

toxic if Ammonia

Question 2

What type of amino acid is generally found in skeletal muscle?

Answer 2

Branched chain hydrophobic

Question 3

How is alanine made into a more useful product?

Answer 3

1. Aminotransferase converts alanine to pyruvate

2. Paired with reaction to convert alphaketoglutamate to glutamate

Question 4

How is glutamate made into a more useful product?

Answer 4

Aminotransferase then glutamate dehydrogenase to form a-ketoglutamate

Question 5

Why are pyruvate and a-ketoglutamate more useful products?

Answer 5

Can be used for gluconeogenesis

Question 6

How can leucine be converted to a more useful product?

Answer 6

1. Aminotransferase used to convert leucine into a-ketoacid to acyl coA to acetyl coA
2. Oxidation of acetyl coA produces NADH and FADH2
3. Hydration then cleavage

Question 7

Outline amino acid catabolism in fed state

Answer 7

Excess aa catabolised

• in muscle to branch-chained
• in liver coverted to glucose
• in small intestine : digestion + circulation -> glutamine

Question 8

Outline amino acid catabolism in starvation

Answer 8

1. Release of aa in blood + muscle
2. Liver aa -> glucose and ketone bodies
3. Small intestine -> glutamine from circulation
   (aa used mainly in beginning and end stages)