Diseases/Enzyme Deficiencies + AA Flashcards Preview

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Flashcards in Diseases/Enzyme Deficiencies + AA Deck (52):
1

von Gierke

glucose-6-phosphatase

2

Pompe

lysosomal alpha-1,4-glucosidase (acid maltase)

3

Cori

debranching enzyme (aplha-1,6-glucosidase)

4

McArdle

skeletal muscle glycogen phosphorylase

5

Fabry's dz def/accum substrate

alpha-galactoside A
ceramide trihexoside

6

Gaucher's dz def/accum substrate

glucoceribrosidase
glucocerebroside

7

Niemann-Pick dz def/accum substrate

sphingomyelinase
sphingomyelin

8

Tay-Sachs dz def/accum substrate

hexosaminidase A
GM2 ganglioside

9

Krabbe's dz def/accum substrate

galactocerebrosidase
galactocerebroside

10

metachromatic leukodystrophy def/accum substrate

arylsulfatase A
cerebroside sulfate

11

Hurler's dz def/accum substrate

alpha-L-iduronidase
heparan sulfate, dermatan sulfate

12

Hunter's dz def/accum substrate

iduronate sulfatase
heparan sulfate, dermatan sulfate

13

essential fructosuria

fructokinase

14

fructose intolerance + tx

aldolase B - accum of F-1-P
tx = exclude fructose + sucrose

15

galactokinase deficiency

galactokinase - galactitol accum (from galactose --> galactitol by ALDOSE REDUCTASE)

16

classic galactosemia + tx

galactose-1-phosphate uridyltransferase - accum of galactitol and galactose-1-phosphate
tx = exclude galactose + lactose

17

tissues w/ ONLY aldose reductase activity

schwann cells
retina
kidneys

(glucose --> sorbitol) - causes osmotic damage

18

tissues w/ both aldose reductase and sorbitol DH activity

liver
lens
overies
seminal vesicles (most active)

sorbitol DH converts sorbitol to fructose

19

glucogenic essential AA

Met
Val
His

20

glucogenic/ketogenic AA

Ile
Phe
Thr
Trp
Tyr (not essential)

21

Ketogenic AA

Lys
Leu

22

Acidic AA

Asp
Glu

negatively charged

23

basic AA

Arg
Lys
His

24

positively charged basic AA

Arg
Lys

25

NO charge basic AA

His

26

MOST basic AA

Arg

27

alkoptonuria

homogentisic acid oxidase - tyrosine --> fumarate

28

albinism

tyrosinase (no melanin synth)

29

3 causes of homocystinuria

1) cystathione synthase (tx = decrease Met, increase Cys; increase vit B12, folate)
2) decreased affinity for pyridoxal phosphate (tx = increase B6)
3) homocysteine methyltransferase (req B12)

30

maple syrup urine disease

alpha-ketoacid DH (B1)

31

hyperchylomicronemia

LPL or altered apoCII

32

abetalipoproteinemia

MTP (microsomal TG transfer protein) gene mutation
deficiency in apoB48 + B100

33

tryptophan derivatives

niacin (via B6)
serotonin (via BH4) --> melatonin

34

histidine derivatives

histamine (via B6)

35

glycine derivatives

porphyrin (via B6) --> heme

36

Arg derivatives

**creatine
**urea
**NO
agmatine

37

glutamate derivatives

GABA (via B6)
glutathione

38

leucine derivatives

catabolized to acetoacetate and acetyl-CoA

39

succinyl-CoA made of what 2 AA?

Val + Ile

40

cofactor req for Phe --> Tyr

THB (reduced via dihydropteridine reductase)

41

cofactor req for Tyr --> Dopa

THB (reduced via dihydropteridine reductase)

42

cofactor req for Dopa --> Dopamine

vit B6

43

cofactor req for Dopamine --> NE

vit C

44

cofactor req for NE --> epinephrine

SAM

45

cofactor + enzyme req for homocysteine --> Met

homocysteine methyltransferase (w/ B12)

46

cofactor + enzyme req for homocysteine + _______ --> cystathionine (pre-Cys)

cystathionine synthase (w/ B6)
______ = serine

47

Met can be broken down to?

succinyl-CoA + SAM

48

homocystinuria findings

increased homocysteine in urine
mental retardation
osteoporosis
Marfinoid habitus (w/ lens sublux downward, not upward)
atherosclerosis (from hypercoag state)

49

what activates muscle glycogen phosphorylase kinase?

Ca2+/calmodulin

50

glycogen BRANCHES have what bonds?

alpha(1,6)

51

glycogen LINKAGES have what bonds?

alpha(1,4)

52

only 2 X-linked recessive lysosomal storage diseases?

Fabry's disease
Hunter's synd