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1

tetrahydrobiopterin

used as cofactor in synthesis of tyrosine (phe-->tyr), dopamine (Tyr-->dopa), serotonin (tryptophan-->serotonin), and nitric acid
via dihydrobiopterin reductase
(def an uncommon cause of PKU)

2

Cystic fibrosis

deletion of PHE at position 508 of CFTR gene
leading to defective protein-therefore less Cl transmembrane Cl channels

3

MSH2 MLH1

Code for MUT L and Mut S
Mistmatch repair gene mutations
account for >90% Lynch (HNPCC) genetic defects

4

sorbitol dehygrogenase

converts sorbital (made via glucose and aldose reductase) to fructose,
deficient in schwann cells, retinal and renal papilla leading to an accumulation in of sorbital
in lens the forward reaction has much less favorable kinetics and therefore can only keep up when small amounts of glucose are being converted to sorbitol
in states of hyperglycemia sorbital accumulates and cause deposits on lens and cataract formation

5

AAs on T arm of tRNA

thymine, cytosine, pseudouracil

6

sickle cell anemia gene defect

pt mutation in the 6th codon of the beta gene leading to valine (hydropobic) substitute for glutamic acid (hydrophilic)
-allowing for hydrophobic interactions and causing hb to aggregate in anaerobic conditions (more specifically bulging in beta chain fits in alpha chain hydrophobic region)

7

aldolase B def

fructose intolerance
metabolizes fructose 1 p to DHAP and glycerol--prevents glycogenolysis and gluconeogenesis
avoid fructose and sucrose (glucose+fructose)

8

mitochondrial metabolic pathways

beta oxidation of fatty acids, ketogenesis, TCA cycle, parts of urea cycle, pyruvate carboxylation

9

AA deriv of NO

arginine

10

AA deriv of urea

arginine and aspartate

11

AA deriv of Heme

glycine and succinyl CoA

12

AA deriv of creatinine

Glycine + arginine + SAM

13

AA deriv of GABA

glutamate

14

AA deriv of glutathione

Glutamate

15

AA deriv of pyrimidines

Glutamate + Aspartate

16

AA deriv of purines

Glutamate + Aspartate + Glycine

17

AA deriv of histamine

histidine

18

AA deriv of dopamine

Phe-->tyrosine-->Dopa-->dopamine

19

AA deriv of melatonin

Tryptophan-->serotonin-->melatonin

20

AA deriv of niacin

tryptophan

21

AA deriv of Melanin

Tyrosine

22

alpha galactosidase A def

Fabrys disease
accumulation of ceramide trihexoside
ancoparesthesias, angiokeratomas, heart/renal disease

23

DNA methylation at CpG islands

represses transcription

24

histone methylation

reversible represses DNA transcription

25

histone acetylation

relaxes DNA coiling and allows for transcription

26

GAG AAs

necessary for purine synthesis
Glutamine
Aspartate
Glycine

27

orotic acidura

defect in pyrimidine production
-hypochromic
megaloblastic anemia
growth retardation
excretion of high amounts of orotic acid in the urine

28

methotrexate/trimethoprime.pyrimethamine

all inhibit dihydrofolate reductase

29

adenosine deaminase deficiency

major cause of SCID
necessary for purine metabolism
leads to accumulation of adenosine which is toxic to lymphocytes
prevents DNA synthesis

30

Lesch Nyhan syndrome

defective absent HGPRT (hypoxanthine guanin phosphoribosyltransferase)
which converts gunaine to GMP and hypothanxine to IMP
excess uric acid production and de novo purine synthesis
-HGPRT
hyperuricemia
Gout
Pissed off (self mutilation, aggression)
Retardation
dysTonia
treatment: allopurinal or febuxostat (2nd line)

31

allopurinol/febuxostat

blocks conversion of hypoxanthine to xanthine and xanthine to uric acid

32

fluoroquinolones mech

inhibit topoisomerase II and IV

33

DNA pol III

5'-3' synthesis, 3'-5' exonuclease

34

DNA pol I

prok only
same as DNA pol III but can excise RNA primer

35

sickle cell dz mutation

missense substitution of glutamic acid with valine

36

duchenne muscular dystrophy mutation

frameshift-resulting in truncated nonfuncitonal dystrophin protein

37

DNA repair of bulky helix distorting lesions

nucleotide excision repair
defective in xeroderma pigmentosa
-cannot fix thymine dimer induced by UV light
-increase aging, skin cancer (squamous cell carcinoma and malignant melanoma)
in G1 phase

38

DNA repair of single NT mistakes

Base excision repair
-glycosylase removes bad base creating an AP (apurinic/apyrimidic) site
-endonuclease cleaves 5' site
-lyase cleaves 3' site
-DNA pol fills in, ligase seals

39

mismatch nucleotides

-repair of newly synthesized strand
MUT S detects mismatch and recruits MUT L-exonucelase removes mismatch and DNA pol fills
-defective in HNPCC
in G2 phase
-

40

DNA repair of double stranded breaks

nonhomologous end joining
-2 ends of DNA are brought together, may lose some DNA
-defective in ataxia telangiectasia and Fanconi anemia
-hypersensitive to ionizing radiation

41

ataxia telangiectasia

defective nonhomoloug DsDNA repair
-get cerebellar atrophy and repeated sino/pulmonary infections
-

42

amantia phalloides

mushroom cap
causes severe hepatotoxicity
-inhibits RNA pol II (makes mRNA)--[Pol I makes rRNA and III makes tRNA) -none have proofreading funciton

43

rifampin

inhibits RNA pol in prokaryotes

44

actinomycin D

inhibits RNA pol in euk and prok

45

p bodies

mRNA quality control, contain exonucleases, decapping enzymes and microRNAs -mRNA may be stored in P bodies and not used till much later

46

anti smith antibodies

highly specific for SLE
antibodies against snRNPs (part of splicesome that take introns out of mRNA)

47

thymine pseudourasil cytosine

T arm of tRNA
necessary sequence for binding with ribosome

48

D arm of tRNA

contains dihydrouracil necessary for tRNA recognition by correct amino-acyl tRNA synthetase

49

Li Fraumeni syndrome

have defect in p53, Rb tumor suppresors which normally regulate G1-->S phase progression

50

SER high in

liver, steroid hormone producing cells of adrenal cortex and gonads

51

mannose 6 phosphate signal

added by golgi-signals protein to lysosome

52

golgi modifications on proteins

modifies N-oligosaccharides on asparagine and adds O-oligosachhardises on serine and threonine

53

coarse facial features, clouded cornea, restricted joint movement,
- high lysosomal plasma levels

I cell disease
-defective N acetylglucosaminyl-1 phosphotransferase that leads to inability of golgi to add mannose signal to proteins
(usually fatal in childhood)

54

COPI
COPII
Clarthrin

COPI: retrograde--golgi trans--cis--ER
COPII: anterograde-ER--Cis--trans
Clathrin: endosomes -receptor mediated endocytosis-LDL receptor activity

55

dyenin

microtubule associated carrier protein
works in retrograde fashion from + to - mt end

56

kinesin

microtubule associated carrier protein, works in anterograde fashion from - to + ends

57

int filaments staining
Vimentin
Desmin
cytokeratin
GFAP
Neurofilaments

vimentin-connective tissues
desmin-muscle
cytokeratin-epithelial tissues
GFAP-neuroglia
neurofilments-neurons

58

kartagener syndrome

primary ciliary dyskinesia
-immotile cilia due to dyenin arm defect
-infertile-no motile sperm and fallopian tube defect, bronchiectasis, recurrent sinusitis, situs inversus

59

digoxin/digitoxin

directly inhibit Na/K ATPase which indirectly inhibts Na/Ca exchange, making the cytoplasm have a high Ca content, increasing contractility

60

collagen type I

bone, skin, tendon, cornea
-defective in OI

61

collagen type II

cartilage

62

collagen type III

reticulin-blood vessels, uterus, fetal tissues, granulation tissue
-defect rare-vascular type of Ehler Danlos syndrome

63

collagen type IV

basement membrane, lens, basal lamina
-defective in alport syndrome, auto-antibodies directed against it in good pasture syndrome

64

best reflection of collagen synthesis

glycine-every 3rd residue

65

which step of collagen synthesis requires vitamin C?

hydroxylation of proline/lysine residues

66

menkes

defective collagen cross linking (lysine to hydroxy lysine) due to mt menkes protein leading to decreased copper absorption and therefore decreased activity of lysyl oxidase (needs copper)
-brittle, kinky hair, growth retardation, hypotonia

67

aging wrinkles

decreased collagen and elas tin FORMATION

68

FAVA beans

can precipitate hemolytic anemia in patients with glucose 6 dehydrogenase def. (used in HMP shunt) and therefore do not produce adequate NADPH necessary for RBS protection against ROS (used in reducing glutathione)

69

amyl nitrate

converts hemoglobin into methhemoglobin whic has low affinity for oxygen but high affinity for CN and shunts this away form organelles (mitochondria) where it would induce damage

70

pyruvate kinase deficiency

necessary for the conversion of phosphoenolpyruvate to pyruvate, producing ATP
-without it RBCs are hemolyzed bc of the insufficinect amount of ATP generated to maintain RBC cellular structure

71

measles supplementation

vitamin A

72

alkaptonuria

defective homogestisic acid oxidase-blocking tyrosine metabolism to fumarate, get accumulation of homogentistic acid which selectively accumulates in cartilage of ear, nose and turns black, also turns urine black

73

excessive egg white ingestion

leads to biotin deficiencey (avindin found in egg whites binds biotin making it inactive)
-biotin is necessary for the conversion of pyruvate to oxaloacetate in gluconeogeneiss)

74

burning feet syndrome

pantothenic acid deficiency (coenzyme A/vitamin B5)
-impt in the TCA cycle binds with oxaloacetate to form citrate
-also necessary for the production of Vitamin A, D, cholesterol, steroids, heme A, fatty acids, AAs, and proteins
causes feeet dysesthesias, paresthesias, edmea of lower extremities, chronic diarrhea, greasy stool

75

thiamine participates as a cofactor in which glucose metabolic pathways

1. part of pyruvate dehrogenase which converts pyruvate to acetyl coa
2. with alpha ketoglutarate dehydrogenase in the TCA cycle
3. HMP shunt with transketolase converting ribulose 5-p to G3P, F6P, and ribose5P

76

high intracellular NADH in the setting of hypoglycemia

indicative of alcohol ingestion-alcohol serves as a form of energy and through its metabolism creates NADH, high NADH then shunts pyruvate from TCA to lactate

77

cafe au lait spots, polyostotic fibrous dysplasia, percocious puberty, many endocrine abnormalities

McCune Albright Syndrome
-due to defect in G protein signaling, example of mosaicism,
-lethal if mutation occurs before fertilization

78

prader willi

imprinting of maternal gene. chromosome 15, paternal gene then deleted, results in hyperphagia, small gonads, obesity, intellectual disability, hypotonia

79

angelman

imprinting of paternal gene with subsequent maternal gene deleted/mutated, results in inappropriate laughter, seizures, ataxia, severe intellectual disability,

80

autosomal dominant diseases

ADPCKD-PKD1 gene chr 16
FAP-APC gene chr 5
Familial hypercholesterolemia
hereditary hemorrhagic telangiectasia
Hereditary shpherocytosis: defect in spectrin or ankyrn
Huntingtons disease CAG repeat chr 4
Li fraumeni syndrome: abnml Tp53 gene--many malignancies at a very young age
Marfan: defective fibrin gene FBN1 chr 13
MEN associated with RET gene
Myotonic dystrophy
NF1: NF1 ch 17
NF2: NF2 ch 22
tuberous sclerosis:
VHL: deletion of VHL chr 3

81

autosomal recessive diesases

CF, sickle cell anemia, ARpkd, glycogen storage disorderd, kartagener syndrome, mucopolysaccharidoses (except hunter), PKU, sphingolipidoses (except Fabrys) Thalassemia, Wilsons

82

X linked recessive diseases

Be Wise, Fool's GOLD Heeds SIlly Hope
Bruton agammaglobulinemia
Wiskott Aldrich syndrome,
Fabry,
G6PD,
Ocular albinism,
Lesh Nyhan,
Hunter SYndrome,
Hemophilia A and B,
Ornithine transcarbamylase A and B

83

myotonic dystrophy type 1

My tonia, my testicles, my toupee, my ticker
CTG trinucleotide repeat of DMPK gene

84

fragile X syndrome

CGG nucleotide repeat of FMR1 gene
-MR, macroorchidism, joint laxity, pes cavus, MVP, long face with large jaw

85

Trinucleotide expansion diseases

Huntinton (CAG)
myotonic dystrophy (CTG)
fragile X (CGG)
friedrich ataxia (GAA)

86

decreased PAPPA
increased b HCG
increased nuchal translucency

downs syndrome findings in first trimester

87

Decreased estriol
decreased alpha fetoprotein
increased b HCG
increased inhibin A

downs syndrome findigns in second trimester

88

rocker bottom feet, micrognathia, low seat ears, clenching hands,

Edwards syndrome trisomy 18, most die after 1 year

89

decreased PAPPA
decreased b HCG

edwards syndrome (trisomy 18)

90

decrased alpha fetoprotein
decreased bHCG
decreased estriol
decreased PAPPA

edwards, trisomy 18

91

cleft lip/palate, holoprosencephaly, polydacytly, congenital heart disease, rocker bottom feet, micropthamnia

Patau trisomy 13

92

decreased b HCG
decreased PAPPA
increased fetal nuchal translucency

Patau syndrome trisomy 13

93

cardiac abnormalities, epicanthal folds, microcephaly, intellectual disability, mewing sound

cri du chat, congenital deletion of short arm of chromosome 5

94

elfin faces, intellectual disability, hypercalcemia (increased sensitivity to Vitamin D) well developed verbal skills, extreme friendliness to strangers, cardiovascular problems

williams syndrome
congenital microdeletion of long arm of chromosome 7

95

CATCH22

microdeletion at chromosome 22q11
C: cleft palate
A: abnormal facies
T: thymic aplasia
C: cardiac defects
H: hypocalcemia 2/2 parathyroid aplasia
DiGeorge: thymic, parathyroid and cardiac defects
Velocardiofacial syndrome: palate, facial, and cardiac defects

96

dry scaly skin, night blindness, immunosuppresion, corneal degeneration, bitot spots on conjunctiva

Vitamin A deficiency

97

vitamin A excess

acute: N/V, blurred vision
Chronic: alopecia, dry skin, pseudotumor cerebri, arthralgias
teratogenic: cleft palate, cardiac abnormalities,

98

high output cardiac failure and LE edema

wet BerIBerI
vitamine B1 def

99

polyneuritis, symmetrical muscle wasting

dry BerIBerI
vitamin B1 def

100

increase in RBS transketolase activity following infusion of thiamine

diagnosis for B1 defiency (wenicke korsakoff/beriberi)

101

cheiliosis and corneal vascularization

vitamin B2 def
riboflavin
necessary for FAD.FMN
B2=2ATP

102

synthesis reactions requiring B6

-cystathione
-heme
-niacin
-histamine
-serotonin
-NE
-epi
-DOPA
-GABA

103

reactions which require Biotin

Vit B7
carboxylation reactions
-pyruvate carboxylase (pyruvate-->oxaloacetate)
-Propionyl carboxylase (propionyl CoA-->methylmalonyl CoA)
-AcetylCoA carboxylase (Acetyl Coa-->Malonyl CoA)

104

causes of B12 deficiency

colbalamin
(have pool stores for years in the liver)
-insufficient intake (veganism)
-malabsorption (celiac sprue, enteritis, Diphyllobothrium latum)
-lack of intrinsic factor (pernicious anemia, gastric bypass)
-absence of terminal ileum (Crohn disease)

105

function of Vitamin C (pathways)

hydroxylation of proline and lysine in collagen synthesis, dopamine Beta hydroxylase (converts dopamine to NE), facilitates absorption of iron by reducing to the Fe2+ ferric state

106

corskcre hair, easy bruising, sollen gums, petechiae, hemarthrosis, anemia, poor wound healing

SCURVY

107

ancillary treatment for methemoglobinemia

vitamin C
-reduces Fe3+ to Fe2+

108

hemolytic anemia, acanthocytosis, posterior column and spinocerebellar tracy demyelination

Vitamin E deficiency
-like B12 without megaloblastic anemia or hypersegmented neutrophils or increased serum MMA

109

dealyed wound healing, altered sense of tase/smell (dysgeusia/anosmia), acrodermatitis enteropathica

Zinc def
-may predispose to alcoholic cirrhosis

110

Kwashiorkor

MEAL
malnutrition
edema
anemia
liver (fatty)

111

Marasmus

calorie malnutrition resulting in muscle wasting, edema loss of sub q fat

112

ATP production from glycolysis with arsenic poisoning

ZERO ATP

113

reactions involving Vitamin b6

transamination (an alpha keto acid joins with an AA to bceome an AA)
and in decarboxylation reactions

114

tender loving care for nancy

cofactors required by branched chain alpha dehydrgoenase, pruvate dehydrogenase and alpha keoglutarate dehydrognease
Thiamine
Lipoate
CoA
FAD
NAD

115

vomiting, rice water stools, garlic breath

arsenic poisoning-->inhibits lipoic acid (a key component of pyruvate dehydrogenase complex)

116

high orotic acid in blood, urine, decreased BUN, tremor, slurred speech, somnolence, vomiting, cerebral edema, blurred vision

high ammonia secondary to ornithine transcarbamylase deficiency
-difference between this and orotic aciduria is no megaloblastic anemia is seen here

117

hereditary dysfunction of PCT preventing absorption of COLA

cystinuria
-cystine
-ornithine
-lysine
-arginine
AT
urinary cyanide-nitroprusside test is diagnostic
-causes hexagonal stone to precipitate
tx: urinary alkalinization (potassium citrate, acetazolamide) and chletating agents (penicillamine)

118

intellectual disability, marfanoid, osteoporosis, lens subluxation, kyphosis, thrombosis, atherosclerosis

homocytinuria
-due to def in cystathionine synthase
treatment: decreased methionin, increase cysteine, increase b12/folate in diet

119

dark connective tissue, brown pigmented sclera, urine turns black on prolonged exposure to air

alkaptonuria
-due to def in homogentisate oxidase
can have debilitating arthralgias -homogentisic acid is toxic to cartilage

120

lactulose give with...

binds ammonia, acidifies GI tract
-given with rifaxamin to decrease colonic ammoniagenic bacteria
-benzoate or phenylbutyrate decrease ammonia by binding and causing its excretion

121

developmental delay, corneal clouding, gargoylism, airway obstruction

hunters
deficiency of alpha L iduronidase
get accumulation of heparan suflate dermatan sulfate

122

developmental delay, gargoylism, aggressive behavior, airway obstruction

hurlers
-iduronate sulfatase deficiency
get buildup of dermatan and hapran sulfate

123

central and peripheral ataxia with dementia, buildup of cerebroside sulfate

Metachromic leukodystrophy
-def of arylsulfatase A

124

globoid cells, peripheral neruopathy,d evelopmental delya, optic atrophy

Krabbe disease
buildup of galactocerebroside/psychosine due to def of galactocerebrosidase

125

cherry red spot, no HSM, progressive neurodegeneration, developmental delay, lysosomes with onion skin

tay sachs
def of hexosaminosidase A

126

cherry red spot, Hsm, developmental regression, fomay histocytes,

neiman picck
def of sphingomyelinase get accumulation of sphingomyelin

127

pancytopenia, HSM, asecptic necrosis of femur, bone crisis, osteoporosis, lipid laden macrophages that look like crinkled tissue paper

gauchers disease
-def of glucocerebrosidase with accumulation of glucocerebroside

128

acroparesthesia, angiokeratomas, cardiovascular/renal

Fabrys
def of alpha galactosidase A with accumulation of ceramide trihexose

129

hypoketotic hypoglycemia with vomiting, lethargy, seizures, liver dysfunciton

def of medium chain acyl COA dehydrogenase
-disorder of fatty acid oxidation and therefore breakdown to acetyl coa

130

systemic primary carnitine def

cant transport long chain fatty acids into the mitochonria
-toxic accumulation causing weakness, hypotonia and hypoketotic hypoglycemia