New Material

Question 1

Amino acids are used for protein synthesis __ ____

Answer 1

in vivo, only when the protein is needed

Question 2

What happens to excess AA?

Answer 2

catabolized

Question 3

Where do N and C themes occur?

Answer 3

liver

Question 4

N theme

Answer 4

AA deamination and ammonia detoxification. Urea synthesis in mammals

Question 5

C theme

Answer 5

breakdown of carbon skeleton

Question 6

N theme steps

Answer 6

1. remove primary amino group from AA
2. synthesis of alpha-keto acid

3.detoxification of ammonia

Question 7

glutamate dehydrogenase (GDH)

Answer 7

deamination of glutamate, a redox rxn. Plays a role in almost all AA

Question 8

transaminase (aminotransferase)

Answer 8

take AA and α-keto acid to synthesize new AA and new α-keto acid

Question 9

What do almost all transaminases use?

Answer 9

α-ketoglutarate and glutamate

Question 10

What B vitamin do transaminases require for catalytic function?

Answer 10

B6 = pyridoxal phosphate

Question 11

AST

Answer 11

aspartate amino transferase

Question 12

ALT

Answer 12

alanine amino transferase

Question 13

What do AST and ALT levels do?

Answer 13

Should be very low levels in bloodstream. Indicate liver damage

Question 14

AST and ALT are _________

Answer 14

equimolar

Question 15

Normal AST levels

Answer 15

8-50 U/L

Question 16

Normal ALT levels

Answer 16

7-55 U/L

Question 17

What is released faster in liver damage?

Answer 17

AST, almost 2X faster

Question 18

Ratio of AST:ALT to be liver issue

Answer 18

> 2

Question 19

Ratio of AST:ALT to be non-liver issue (but still issue)

Answer 19

> 5

Question 20

Deamination of serine

Answer 20

serine –> pyruvate by serine dehydratase

Question 21

Deamination of threonine

Answer 21

threonine –> α-ketobutyrate by threonine dehydrates

Question 22

Prosthetic group for serine and threonine dehydratase?

Answer 22

pyridoxal phosphate

Question 23

Where does detoxification of ammonia occur?

Answer 23

cytosol, with some steps in mitochondria

Question 24

Where is alanine generated?

Answer 24

muscle