Lecture 9 - Phenylalanine/Tyrosine Example

Question 1

Step 1

Answer 1

Phenylalanine -> tyrosine

Question 2

Step 2

Answer 2

Tyrosine -> p-hydroxyphenyl pyruvate

Question 3

Step 3

Answer 3

P-hydroxyphenyl pyruvate -> homogentisate

Question 4

Step 4

Answer 4

Homogentisate -> maleyl acetoacetate

Question 5

Step 5

Answer 5

Maleyl acetoacetate -> fumaryl acetoacetate

Question 6

Step 6

Answer 6

Fumaryl acetoacetate -> acetoacetate

Question 7

Step 7

Answer 7

Acetoacetate -> acetoacetyl CoA

Question 8

Step 8

Answer 8

Acetoacetyl CoA -> acetyl CoA

Question 9

Enzyme of step 1

Answer 9

Phenylalanine hydroxylase

Question 10

Enzyme of step 2

Answer 10

Tyrosine aminotransferase

Question 11

Enzyme of step 3

Answer 11

P-hydroxyphenyl pyruvate dioxygenase

Question 12

Enzyme of step 4

Answer 12

Homogentisate 1,2-dioxygenase

Question 13

Enzyme of step 5

Answer 13

Maleyl acetoacetate isomerase

Question 14

Enzyme of step 6

Answer 14

Fumaryl acetoacetase

Question 15

Enzyme of step 7

Answer 15

Beta-keto acyl CoA transferase

Question 16

Enzyme of step 8

Answer 16

Beta-keto acyl CoA thiolase

Question 17

Cofactor of step 1

Answer 17

• NAD+ -> NADH + H+
• Tetrahydrobiopterin -> dihydrobiopterin
• O2 -> H2O

Question 18

Cofactor of step 2

Answer 18

Alpha-ketoglutarate -> glutamate

Question 19

Cofactor of step 3

Answer 19

O2 -> CO2

Question 20

Cofactor of step 4

Answer 20

O2 -> H+

Question 21

Cofactor of step 5

Answer 21

None

Question 22

Cofactor of step 6

Answer 22

• H2O in

- Fumarate out

Question 23

Cofactor of step 7

Answer 23

Succinyl CoA -> succinate

Question 24

Cofactor of step 8

Answer 24

CoA-SH in

Question 25

What happens to the 2 molecules of acetyl CoA that are produced?

Answer 25

Enter the TCA cycle

Question 26

What is step 8 the same as?

Answer 26

The last step of beta-oxidation