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Flashcards in Biochem Deck (101):
1

Histones rich in;

lysine and arginine

2

DNA methylation for old vs new strands

cytosine and adenine

3

Purine synthesis needs

Glycine
Aspartate
Glutamine

4

pyrimidine synthesis needs:

Aspartate
Glutamine (to make carbamoyl phosphate)

5

ADA SCID mechanism

Cant turn Adenosine to Inosine, so all other base production is allosterically inhibited (ribonucleotide reductase)

6

AA with one 1 codon

Methionine (AUG)
Tryptophan (UGG)

7

DNA pol III vs pol I

Pol III = 5-3 synthesis with 3-5 proofreading exonuclease; most of TC
Pol I = 5-3 synthesis, 3-5 proofreading AND 5-3 exonuclease to chew the primer off; TC joining segments

8

RT in humans

Telomerase (shortened telomere sin Bloom)

9

mRNA read:

5'-3'

10

Thing missing in these diseases:
- XP
- HNPCC
- FA, AT

- XP = NER
- HNPCC = MMR
- FA, AT = NHEJ

- BER for spontaneous/toxic deamination

11

Phase of fixing stuff:
- NER
- BER
- MMR

- NER = G1
- BER = any
- MMR = G2

12

fMET =

prok start codon
also PMN chemotaxis

13

a-amantadin

inhibits RNA pol II (mRNA) and hepatotoxicity and nephrotoxicity

14

rifampin vs actinomycinD

rifampin = proks
dactinomycin = proks and euks

both inhibit RNA pols

15

P-bodies

cytoplasmic mRNA QC

16

CDK expression

constitutive but inactive until cyclin binds

17

Golgi:
@ asparginine
@ serine
@ threonine

Asp = modificatoin of N-oligosaccharides
Ser = addition of O-oligosaccharides
Thre = addition of O-oligosarcharides

18

mannose-6-P

for trafficking to lysosome
problem = 1-cell disease: coarse face, clouded cornea, restricted joint movements, high plasma lysosomal enzymes, fatal in childhood

19

Peroxisome

VLCFS
BCFA
AA

20

Prooteasome

mutations in Parkinsons

21

Vimentin =

IF of messenchyme (CT)

22

Desmin =

IF of muscle

23

MT drugs:

Greisofulvin
Paclitaxel
Vincristine/vinblastine
colchicine
Mebendazole

24

Ouabain

inhibits K+ binding site of Na/K ATPase

25

Col II =

cartilage, NP, vitreous body

26

Col III =

reticulin - BV, skin, ED

27

hydroxylatoin vs glycosylation vs. crosslinking of collagen

hydroxylation = proline and lysin, with vit C
Glycosylation = hydroxylysine
crosslinking = lysin to hydroxylysin with Cu

28

FiSH

microdeletions
fluorescent DNA or RNA, if it light up it bound the DNA of interest, which mean it is NOT deleted

29

Known-down via

dsRNA, transfected, separates, binds and degrades mRNA target

30

a1-AT genetics

codominance

31

McCune Albright syndrome

Need somatic mosaicism to survive (lethal if mutation occurs before fertilization thus affecting all cells)

Unilateral cafe-au-lait, polyostoic fibrous dysplasia, precocious puberty, endocrien problems

32

Heteroplasmy

both normal and mutates mtDNA; variable expression of MT disease

33

Osler-Weber-Rendu

hereditary hemmorhagic telangectasias - bleed
AD

34

SBLA cancer syndrome

Li-Fraumeni
p53 mutation - AD
sarcoma, breast, lung, adrenal

35

MEN inheritance

AD

36

marfans inheritance and lens subluxation and heart stuff

AD
up and out
MEDIA - MVP, aortic dissectoin

37

NF1

cafe-au-lait, cutaneous neurofibromas, optic gliomas, lisch nodules, pheo

38

NF2

Bilateral acoustic schwannomas, meningiomas, ependymomas, juvenile cataracts

39

complete penetrance, variable expressivity

tuberous sclerosus - hammartomas

40

increased immunoreactive trypsinogen

newborn screen for CF

41

COD DMD

dilated cardiomyopathy

42

DMD blood

high CK and aldolase

43

Alterations of dystrophin gene

XR - Frameshift (del, dupl, nonsense) = DMD
XR - non-frameshift insertion = beckers
AD - CTG expansion = myotonia-1

44

myotonia-1

myotonia/muscle wasting
frontal balding
testicular atrophy
arrythmia

45

fragile x
freidreich ataxia
huntingtons
myotonia

fragile x - CGG - 5'UTR
freidreich ataxia - GAA - intron
huntingtons - CAG - exon
myotonia - CTG - 3'UTR

46

Downs profile

low aFP
high bHCG
low estriol
high inhibin A

47

edwards profile

trisomy 18
low everything

48

patau profile

low everything with increased nuchal translicency

49

Williams syndrone

elfin
hypercalcemia
high verbal skills
super friendly
CV problems
intellectual disability

50

vitamin rx for measles

vitamin A

51

Chronic vitamin A toxicity

dry skin
pseudotumour cerebri
alopecia
hepatotoxicity and enlargement
arthalgias

52

dx B1 deficiency

increase transketolase activity post-B1 infusion

53

B2 deficiency

Chelosis
Corneal vascularization

54

how to make b3

tryptophan (decrease with hartnups or malignant carcinoid)
B2
B6 (decrease with INH)

55

flushing of B3 via:

PROSTAGLANDINS (not histamine)

56

B Vitamin deficiencies and key finding:
B1
B2
B3
B5
B6
B7

B1 - W-K or beri-beri
B2 - chelosis, corneal vasc
B3 - pellagra
B5 - adrenal insufficiency
B6 - convulsions, sideroblastic anemia
B7 - rare; seen with eating raw egg whites

57

vitamin for Fe absorption

Vit C
turn 3+ to 2+ (so also used for initial metHb rx)

58

vitamin + warfarin

E - enhances effects
K = target

59

Fomepizole

inhibits alcohol DH for ethylene glycol or methanol poisoning

60

FBPase - fasting state

fasted = glucagon = Phosphorylate FBPase-2 (active) = turn f-2,6-bisP to F-6-P = gluconeogenesis (and less glycolysis)

61

Arsenic poisoning

Inhibits lipoic acid, so dont have the dehydrogenase complexes
s/s = vomiting, rice-water stools, GARLIC BREATH
No ATP made in glycolysis

62

Kreb's cycle

"citrate is krebs starting substance for making oxaloacetate"

63

purely ketogenic AAs

Leucine
Lysine

64

ETC inhibitors

I - rotenone
III - antimycin A
IV - CO and cyanide

65

ATP synthesis inhibitors (complex V)

Oligomycin - INCREASES the proton gradient (as opposed to uncouplers)

66

FA creating glucose

only odd chain FA because propionyl CoA can enter at succinyl coA, but even chain can only be acetyl coA

67

PPP for which reactions:

reductive: glutathione in RBCs, FAS, Cholesterol synthesis

68

Essential fructosuria

Fructokinase - benign

69

Fructose intollerance

aldolase B - hypoglycemia, jaundice/cirrhosis, vomiting, fail to thrive

70

Galactokinase deficiency (mild galactosemia)

galactokinase - infantile cataracts (no tracking or social smile) via galactitol

71

Classic /severe galactosemia

galactose-1-P uridyl transferase - jaundice/cirrhosis, vomiting, fail to thrive, cataracts, intellectual disability

72

amount of sorbitol dehydrogenase in cell types

None = schwann, retina, kidney
Little = lens

73

Essental AA: gluconeogenic, both, and ketogenic

Gluco: MVH
both: IFTY
keto: LK

74

Treatments for hyperammonemia

lactulose - trap NH4+
Rifaximin - decrease colonic amminogenic bacteria
benzoate and phenylbutyrate - bind AAs causing excreton

75

NAG or CPS-I deficiency

poor temprature and respiratory control, poor feeding, developmental delay, intellectual disability

76

OTC deficiency

XR
MC urea cycle disorder
buildup carbamoyl phosphate, so turn it into orotic acid
s/s = orotic acid in blood and urine, low BUN (urea) .: hyperammonemia

*NO megaloblastic anemia like in orotic aciduria (cant turn orotic acid into UMP for pyrimidine de novo)

77

hyperammonemia

Somnolence
Slurred speech
Asterixis
Vomiting
Vision blurry
Edema (cerebral)

78

Catecholamine cofactors; others

Catecholamines: BH4 BH4 B6 VitC SAM

Everything else = B6 except:
- Serotonin also BH4
- Niacin also B2
- NO = BH4

79

Homocysteinuria s/s

marfanoid with hyphoscoliosis and lens subluxatin (but down and in)
thombosis
AS - stroke and MI
intellectual disability
OP

80

b-glucuronidase

released by injured hepatocytes and bacteria when GB infected (asians)
hydrolyzed conjugated bilirubin causing unconjugated brown pigmented bilirubin stones

81

Bilirubin uptake and export transporters

Uptake = passive via OATP
release = active = ATP binding cassette MRP2

82

reversible/non-oxidative enzymes in PPP

transketolase
Phosphopentose isomerase

ribulose-5-p ribose-5-P/G3P/F6P

83

B-vitamin general actions:
B1
B2
B3
B5
B6
B7

B1 = dehydrogenase complexes + transketolase (with B2, B3, B5, lipoic acid)
B2 = FAD/FMN
B3 = NAD
B5 = CoA
B6 = Transaminases, DEcarboxylations, glycogen phosphorylase, PLP
B7 = Carboxylases

84

Von geirkes (I)

glucose-6-phosphatase - liver
severe fasting hypoglycemia and hepatomegaly, high uric acid, high lactate
frequent glucose/cornstarch meals; avoid fructose and galactose

85

McArdle (v)

Glycogen phosphorylase - muscle (myophosphorylase)
Cramps, myoglobinuria, arrhythmias
Rx = B6

86

Cori/Forbes (III)

Debranching enzyme (a-1,6-glucosidase)
Like Von Geirkes but mild and no lactic acidemia

87

Pompe

lysosomal a-1,4-glucosidase (acid maltase) - lysosomes
Caridomegally, hypertrophic cardiomyopathy, ecercise intolerance

88

Zellwegers

peroxisomal disorder
no a-ox (some branched) or VLCFA
poor CNS myelination, seizure, hypotonia, H-megaly, death in months

89

Refsums

peroxisomal disorder
no a-ox - phytanic acid accumulates
cerebellar, peripheral neuropathy
avoid phytanic acid

90

citrate shuttle:

gets citrate out into cytoplasm for FAS

91

Carnitine shuttle

Brings (VLCFs) fatty-acyl-CoAs into mitochrondria for b-oxidation (FAO)

Deficiency causes toxic accumulation in cytosol --> weakness, hypotonia, hypoketotic hypoglycemia

92

hypoketotic hypoglycemia

1' carnitine deficiency (LCFA)
MCAcyl-CoA dehydrogenase deficiency

93

urine test for ketones detects:

acetoacetate

94

more common ketone

b-hydroxybutyrate

95

Apo-C-II

activates LPLase

96

Apo-A-I

Activates LCAT

97

I - hyperchylomicronemia

AR
Via LPL or C-II deficiency
s/s = high TG (pancreatitis) and cholesterol (HP-megaly, eruptive/pruritic xanthomas)
NO CV risk because no increase in LDLs

98

IIa - familial hypercholesterolemia

AD
Hetero LDL ~300
Homo LDL > 700
Young AS and MI, achiles xanthomas, corneal arcus

99

IV-hypertriglyceridemia

AD
Hepatic overproduction of VLDL
s/s = high TG -> pancreatitis

100

Where is GTP made in TCA

succinyl-CoA to succinate
(used by PEP-CK)

101

Which essential AA can donate directly into urea cycle

Aspartate (aspartic acid; D)