Amino Acid Metabolism 10/24/16 German TEST #3

Question 1

What are the essential Amino Acids?

Answer 1

• Isoleucine
• Leucine
• Valine
• Phenylalanine
• Tryptophan
• Histidine
• Lysine
• Threonine
• Methionine

Question 2

What are the non-essential amino acids?

Answer 2

• Alanine
• Glycine
• Proline
• Tyrosine
• Aspartic Acid
• Glutamic Acid
• Arginine
• Serine
• Cysteine
• Asparagine
• Glutamine

Question 3

What are the four fates of dietary amino acids?

Answer 3

• Protein synthesis
• Energy production
• Biosynthesis
• Urea excretion

Question 4

What are the three fates of dietary amino acids?

Answer 4

• Used for protein synthesis within cells
• Catabolized for energy within cells
• Transported to the liver and excreted

Question 5

Where does most amino acid catabolism occur?

Answer 5

-Liver

Question 6

What are four metabolically important amino acids?

Answer 6

• Glutamate
• Glutamine
• Aspartate
• Alanine

Question 7

What does ammonia do to K+ uptake?

Answer 7

-Disrupt astrocyte K+ uptake

Question 8

What does the high extracellular K+ levels do to GABA receptors?

Answer 8

Prevents GABA inhibition

Question 9

How are amine groups stabilized in the body?

Answer 9

• Urea

- Uric acid

Question 10

What are two common amino acid catabolism reactions?

Answer 10

• Transaminase reactions

- One-carbon transfers

Question 11

What does PLP (pyridoxal phosphate) have to do with transaminase reactions?

Answer 11

• Common coenzyme

- Carrier of amino groups

Question 12

What is an example of a transaminase reaction?

Answer 12

A-Ketoglutarate to Glutamate

Question 13

How is intracelluar ammonia buffered?

Answer 13

By converting glutamate to gluatamine

Question 14

What is the formula for ammonia?

Answer 14

NH3

Question 15

Why do you convert glutamate to glutamine to transport in the blood?

Answer 15

Glutamine is non-toxic

Question 16

What enzyme converts glutamate to glutamine?

Answer 16

Glutamine synthetase

Question 17

How does alanine help transport ammonium to the liver?

Answer 17

Glucose-Alanine cycle

Question 18

How is alanine made?

Answer 18

By an aminotransferase cycle with pyruvate to alanine from glutamate to A-ketoglutarate

Question 19

When does the glucose alanine cycle occur?

Answer 19

-Anaerobic states

Question 20

What other cycle does the glucose alanine cycle coincide with?

Answer 20

Cori Cycle

Question 21

What does the urea cycle ultimately secrete?

Answer 21

Liver Nitrogen

Question 22

How many steps are in the urea cycle?

Answer 22

4

Question 23

What is a molecules that is absolutely necessary for the urea cycle to occur?

Answer 23

Ornithine

Question 24

What is urea?

Answer 24

A stable amine-rich molecule

Question 25

T/F

The urea cycle is ATP dependent

Answer 25

True

Question 26

Where does the urea cycle require enzymes from?

Answer 26

The mitochondria and cytoplasm

Question 27

What three amino acids are involved with taking amine groups to the mitochondria?

Answer 27

• Alanine
• Glutamine
• Glutamate

Question 28

Once you have the amine group inside the mitochondria what two molecules are produced?

Answer 28

• Aspartate

- Carbamoyl phosphate

Question 29

What molecule is used a precursor to make aspartate?

Answer 29

Oxaloacetate

Question 30

What removes just the Ammonium from glutamate?

Answer 30

-Glutamate dehydrogenase

Question 31

What makes carbamoyl phosphate?

Answer 31

• Bicarbonate
• ammonium
• ATP

Question 32

What takes the amine group from carbamoyl phosphate in the mitochondria?

Answer 32

Ornithine

Question 33

When ornithine takes the amine group from carbamoyl phosphate what does it become?

Answer 33

-Citrulline

Question 34

What gives citrulline another amine group in the cytoplasm?

Answer 34

-Aspartate

Question 35

When citrulline receives an amine group from aspartate what does it become?

Answer 35

-Argininosuccinate

Question 36

What is a side product released from argininosuccinates conversion to arginine?

Answer 36

-Fumarate

Question 37

What is released from the conversion of arginine to ornithine in the urea cycle?

Answer 37

-Urea

Question 38

What are the two levels of urea cycle regulation?

Answer 38

• Increased synthesis of the enzymes involved in the urea cycle
• Allosteric N-acetylglutamate regulation

Question 39

T/F

The citric acid cycle and urea cycle are not directly linked

Answer 39

False

They are linked to each other

Question 40

How is the CAC and Urea cycle linked?

Answer 40

The aspartate-arginino-succinate shunt

Question 41

What are glucogenic amino acids?

Answer 41

-Amino acids that can be converted into glucose

Question 42

What are ketogenic amino acids?

Answer 42

-Amino acids that can be converted into ketone bodies

Question 43

What are three important one carbon transfer reactions cofactors?

Answer 43

• Biotin
• Tetrahydrofolate
• S-Adenosylmethionine (These are vitamins)

Question 44

What are six amino acids that are degraded to pyruvate?

Answer 44

• Tryptophan
• Alanine
• Cysteine
• Serine
• Glycine
• Threonine

Question 45

What are seven amino acids that degrade to Acetyl-CoA?

Answer 45

• Tryptophan
• Lysine
• Phenylalanine
• Tyrosine
• Leucine
• Isoleucine
• Threonine

Question 46

What are five amino acids that are degraded to A-Ketoglutarate?

Answer 46

• Glutamate
• Glutamine
• Proline
• Arginine
• Histidine

Question 47

What are four amino acids that are degraded to succinyl-CoA?

Answer 47

• Methionine
• Isoleucine
• Valine
• Threonine

Question 48

What are two amino acids that are degraded to oxaloacetate?

Answer 48

• Asparagine

- Aspartate

Question 49

What two pathways can tryptophan enter?

Answer 49

• Pyruvate

- Acetyl CoA

Question 50

What three pathways can threonine enter?

Answer 50

• Pyruvate
• Acetyl-CoA
• Succinyl CoA

Question 51

What two pathways can Isoleucine enter?

Answer 51

• Succinyl-CoA

- Acetyl-CoA

Question 52

What two pathways can Phenylalanine enter?

Answer 52

• Acetyl-CoA

- Fumarate

Question 53

What two pathways can tyrosine enter?

Answer 53

• Fumarate

- Acetyl-CoA