Amino Acids Part 2

Question 1

What major compounds derive nitrogen from amino acids?

Answer 1

Nitric oxide, hormones, neurotransmitters, nicotinamide, heme, creatin phosphate, and nucleotides

Question 2

Where does the conversion of ammonia to urea take place?

Answer 2

Liver

Question 3

FIRST STEP IN General scheme of amino acid catabolism

Answer 3

1. remove amino group that is used to synthesize new nitrogen compounds or excreted as urea

Question 4

SECOND STEP in general scheme of amino acid catabolism

Answer 4

incorporation of the carbon atoms into compounds that can enter the TCA cycle

Question 5

Are the transaminase reactions reversible? Why

Answer 5

Yes, allows the inter-conversion between amino acids keeping their concentrations balanced

Question 6

Ammonia is what to living organisms?

Answer 6

Ammonia is highly toxic & must be eliminated safely

Question 7

What is the function of the UREA cycle

Answer 7

Converts:

1. one molecule of free ammonia (from glutamic acid)
2. one amino group from aspartate into urea and fumarate

Question 8

Where does the free ammonia in the urea cycle come from?

Answer 8

Glutamic acid

Question 9

where does the amino group in the urea cycle come from

Answer 9

Aspartate..which is converted into urea and fumarate

Question 10

What is the connection between the urea cycle and the TCA cycle?

Answer 10

Through the product of fumarate during the urea cycle

Question 11

What is used to transport nitrogen from peripheral tissues to the liver?

Answer 11

Alanine

Question 12

What is alanine converted into, in the liver?

Answer 12

Alanine is converted into pyruvate with the nitrogen incorporated into urea

Question 13

What facilitates the conversion of amino acids into glucose?

Answer 13

Glucose-alanine cycle

Question 14

What is released by muscle into the blood?

Answer 14

Alanine & glutamine

Question 15

How % does alanine & glutamine account for going into the blood?

Answer 15

50%

Question 16

Where does the conversion of ammonia into carbamoyl phosphate occur?

Answer 16

Mitochondria

Question 17

What conversion happens in the mitochondria?

Answer 17

Conversion of ammonia into carbamoyl phosphate

Question 18

Urea Cycle activity

Answer 18

Can be lethel when effected. Several genetic defects affect the urea cycle

Question 19

Whats good treatment if the urea cycle is affected?

Answer 19

Use of a compound that reacts with amino groups and remove them from the body

Question 20

Glucogenic amino acids can be metabolized into what?

Answer 20

3 carbon molecules that can be used to synthesize glucose

Question 21

What are ketogenic amino acids metabolized into?

Answer 21

2 or 4 carbon structures

Question 22

Defects in amino acid metabolism

Answer 22

can become an inherited disease

Question 23

Maple Syrup urine disease (MSUD)

Answer 23

inability to metabolize branch chain amino acids

Question 24

What is Phenylkeonuria?

Answer 24

a deficiency of phenylalanine hydrooxylase that converts phenylalanine to tyrosine

Question 25

What are other defects of the aromatic amino acid metabolism

Answer 25

Alkaptonuria (black urine disease) & albinism

Question 26

What is the first step in polyamine synthesis

Answer 26

decarboxylation of ornithine to make putrescine

Question 27

What is Ornithine decarboxylase (ODC)

Answer 27

the rate-limiting step in polyamine synthesis and has been the target for a number of cancer drugs