Pyruvate Metabolism

Question 1

Pyruvate can become:

Answer 1

1) Lactic acid
2) Acetyl-CoA
3) Alanine
4) Oxaloacetate

Question 2

Which path does pyruvate take if no oxygen is present (anaerobic pathway)?

Answer 2

Lactic acid pathway

Question 3

Which enzyme converts Pyruvate to Lactic acid?

Answer 3

Lactate Dehydrogenase (LDH)

Question 4

When is Lactate Dehydrogenase most active?

Answer 4

Low O2 states:
1) Infection
2) Hypoxia/Ischemia
3) Heart failure

Question 5

In which tissues does Pyruvate primarily convert to Lactic acid?

Answer 5

1) Testes
2) Lens
3) WBCs
3) Cornea
4) Medulla (Kidney)
5) RBCs

(Think Lactate When You Can’t Make Respirations)

Question 6

Which enzyme converts Pyruvate to Alanine? (Alanine Aminotransferase Pathway)

Answer 6

ALT

Question 7

Which cofactor is used in the Alanine Aminotransferase Pathway? (Pyruvate -> Alanine)

Answer 7

B6

Question 8

Why does the Cahill Cycle exist?

Answer 8

Because Pyruvate can’t jump between muscle to liver = disguise Pyruvate as Alanine or Glucose

Question 9

What is the main goal of the Cahill Cycle?

Answer 9

Recycle carbons between muscles and liver

Question 10

The conversion of pyruvate to alanine takes place in the:

Answer 10

Muscle

Question 11

Which cofactor is required in the conversion of Pyruvate to Alanine?

Answer 11

Glutamate

Question 12

In the conversion of Pyruvate to Alanine, Glutamate becomes:

Answer 12

Alpha-Ketoglutarate

Question 13

Pyruvate + ___ = Alanine + ___

Answer 13

Glutamate; Alpha-Ketoglutarate

Question 14

Once Alanine goes into the liver, what happens?

Answer 14

The opposite of what happened in the muscle (Alanine + Alpha-Ketoglutarate = Pyruvate + Glutamate)

Question 15

The conversion of pyruvate to glucose takes place in the:

Answer 15

Liver

Question 16

The glucose produced in the liver can then go to the:

Answer 16

Muscle

Question 17

Which enzyme converts pyruvate to oxaloacetate?

Answer 17

Pyruvate Carboxylase

Question 18

Which cofactor does Pyruvate Carboxylase require?

Answer 18

Biotin (B7)

Question 19

Which cofactor does Pyruvate Carboxylase require?

Answer 19

Biotin (B7)

Question 20

What is the goal for converting Pyruvate to Oxaloacetate?

Answer 20

Oxaloacetate can enter:
1) Gluconeogenesis
2) TCA/Krebs Cycle

Question 21

Which enzyme converts Pyruvate to Acetyl-CoA?

Answer 21

Pyruvate Dehydrogenase

Question 22

Why is the conversion of Pyruvate to Acetyl-CoA the most important one?

Answer 22

Because without this conversion, we can’t make Acetyl-CoA, and without Acetyl-CoA we can’t enter the TCA/Krebs Cycle.

Question 23

Why is the conversion of Pyruvate to Acetyl-CoA the most important one?

Answer 23

Because without this conversion, we can’t make Acetyl-CoA, and without Acetyl-CoA we can’t enter the TCA/Krebs Cycle.

Question 24

Which cofactors are required for Pyruvate Dehydrogenase to work?

Answer 24

1) B1
2) B2
3) B3
4) B5
5) Lipoic Acid

Question 25

Which 2 Pyruvate conversions are IRREVERSIBLE?

Answer 25

1) Oxaloacetate
2) Acetyl-CoA

Question 26

Pyruvate’s conversions to Lactic acid and Alanine take place in the:

Answer 26

Cytosol

Question 27

Pyruvate’s conversions to Oxaloacetate and Acetyl-CoA take place in the:

Answer 27

Mitochondria

Question 28

Which of Pyruvate’s conversions take place in the cytosol?

Answer 28

1) Alanine
2) Lactic Acid