Nitrogen Metabolism

Question 1

What AA are affected in Hartnup

Answer 1

Nonpolar

*Tryptophan
Alanine
Phe
Leucine
Isoleucine
Valine
Tyrosine
Glutamine

Question 2

What AA are affected in Cystinuria

Answer 2

Dibasic AA (COAL)

*Cystine
Lysine
Arginine
Ornithine

Question 3

What three molecules are deficient in a patient with Hartnup?

Answer 3

Serotonin
Melatonin
Niacin –> NAD deficiency

Question 4

What enzyme is affected in Classical PKU?

Answer 4

Phe Hydroxylase (PAH)

Question 5

What step is affected in Both types of PKU?

Answer 5

Phe –> Tyr

Question 6

What enzyme is affected in Nonclassical PKU?

Answer 6

THB reductase

Question 7

What enzyme is affected in Tyrosinemia Type I?

Answer 7

FAA Hydrolase

• cabbage smelling
• v. common to test babies

Question 8

Tyrosinemia Type II:

Answer 8

Tyrosine Aminotransferase

Tyr –> Glu

Question 9

Tyrosinemia Type III

Answer 9

P-hydroxyphenylpyruvate

Question 10

Alkaptonuria

Answer 10

Homogentisate oxidase

**Black urine black eye spots and discolored connective tissue

Question 11

Uric acid crystals

Answer 11

Gout

Question 12

GOUT causes

Answer 12

Primary = overproduction of uric acid
Secondary = underexcretion of uric acid
Deposit of sodium urate in joints

Question 13

Treatment for Gout

Answer 13

• Low protein diet
• No meat, alcohol, seafood, beans, lentils
  Allopurinol (inhibits xanthine oxidase)

Question 14

What promotes CPS I?

Answer 14

NAG

Question 15

What 3 transporters can be affected in Hyperammonemia?

Answer 15

Mitochondrial Ornithine carriers
Asp/Glu carrier
Dibasic amino acid transporter

Question 16

Ornithine transcarbamoylase

Answer 16

Orotic aciduria (X-linked)

Question 17

NAGS

Answer 17

Hyperammonemia

Question 18

CPS I

Answer 18

Hyperammonemia

Question 19

Arginiosuccinate Synthetase

Answer 19

Citrulinemia

Question 20

Arginiosuccinate Lyase

Answer 20

Arginiosuccinate aciduria

Question 21

Arginase

Answer 21

Slight hyperammonemia

Question 22

Where is CPS II used?

Answer 22

pyrimidine synthesis

Question 23

What activates CPS II?

Answer 23

PRPP

Question 24

Calcium oxalate crystals

Answer 24

Hyperthyroidism

Question 25

Struvite crystals

Answer 25

Ca/Phosphate imbalance

Question 26

Crystine Crystals

Answer 26

Genetic

Question 27

What enzyme is responsible for conjugating bilirubin?

Answer 27

UGT