A.A. catabolism

Question 1

What 2 A.A. don’t undergo deamination directly?

Answer 1

Lys, Pro

Question 2

> @KG?

Answer 2

Gln, Glu, Arg, His, Pro

Question 3

Histidase deficiency >

Answer 3

Histidinemia: speech difficulty
Limiting His impairs growth

Question 4

> OXAC?

Answer 4

Asn, Asp

Question 5

> Acetoacetate?

Answer 5

Lys, Leu
Ketogenic

Question 6

Lysine metabolism occurs in _

Answer 6

Liver

Question 7

Hyperlysinemia >

Answer 7

Saccharopine DH defect
Mental, physical retardation

Question 8

> Pyruvate?

Answer 8

Ala, Gly, Ser, Cys, Thr

Question 9

Ser > Gly via ?

Answer 9

Serine + THF > Gly + methylene THF via serine hydroxymethyl transferase

Question 10

T/F: Threonine catabolism gives both keto/glucogenic products.

Answer 10

True

Question 11

BCAA catabolism
Where does it occur?

Answer 11

Leu, Ile, Val
Muscle

Question 12

BCKADH needs 5 cofactors

Answer 12

lipoic acid, NAD, FAD, TPP, CoA

Question 13

Maple syrup urine disease

Answer 13

• Defect in BCKADH or cofactors
• Ketoacids accumulate and excreted in urine
• Maple syrup odor

Question 14

Sweaty feet syndrome

Answer 14

• Defect in leu metabolism
• Deficiency in isovaleryl CoA DH
• Isovaleryl CoA > unsaturated acyl CoA
• Accumulation of isovaleric acid

Question 15

Aromatic A.A.

Answer 15

Phe, Tyr

Question 16

Phenylketonuria

Answer 16

• Deficiency in Phe-hydroxylase
• Hyperphenylalaninemia
• Phe accumulates > transamination of Phe > phenyl acetate and phenyl lactate, phenyl pyruvate

Question 17

Alkaptonuria(black urine)

Answer 17

• Deficiency in homogentisic dioxygenase
• HA accumulates, excreted in urine, + O2 > black urine
• Inflammation in joints

Question 18

Albinsim

Answer 18

• Deficiency of tyrosinase isoenzyme in CNS
• Improper hydroxylation of tyr
• Not deficient in dopamine

Question 19

3OH-anthranilic acid is a precursor of

Answer 19

NAD

Question 20

Deficiency in Trp oxygenase/niacin

Answer 20

pellagra

Question 21

Deficiency in kynureninase/B6

Answer 21

• Excretion of kynurenine in urine…green urine

Question 22

SAM is used in (3)

Answer 22

• Melatonin from serotonin
• Epinephrine from nor
• PC synthesis

Question 23

Cysteine can yield many products…

Answer 23

• Pyruvate
• Oxidized cystine
• Cysteic acid > Taurine
• Cysteic acid deamination > PAPS
• B-mercapto-ethyl amine…+ pantothenic acid > CoA

Question 24

Homocystinuria

Answer 24

• Deficiency in cystathionine synthase
• Homocysteine accumulates
• Thiolactone > cardiovascular problems
• Atherosclerosis

Question 25

Homocysteine made from

Answer 25

C skeleton of met without methyl