AA: Disposal of Nitrogen

Question 1

5 enzymes of urea cycle

Answer 1

-in the order that they get used–>carbamoyl phosphate synthetase I, ornithine transcarbamoylase, argininosuccinate synthetase, argininosuccinate lyase, arginase

Question 2

CO2 + NH3+ ATP–>

Answer 2

-carbamoyl phosphate with enzyme carbamoyl phosphate synthase I—-takes 2 molecules of ATP

Question 3

3 AA alpha-keto acid pairs

Answer 3

• alanine/pyruvate
• aspartate/oxaloacetate
• glutamate/alpha-ketoglutarate

Question 4

2 nitrogen enters as ?

Answer 4

-ammonia and aspartate

Question 5

Urea is produced by hydrolysis of what?

Answer 5

-arginine

Question 6

Transaminase acts on all AA except—

Answer 6

threonine and lysine

Question 7

Glutamate dehydrogenase

Answer 7

• can use either NADH or NADPH

- GTP allosteric inhibits glutamate dehydrogenase