Biochem Flashcards
1
Q
Histones rich in;
A
lysine and arginine
2
Q
DNA methylation for old vs new strands
A
cytosine and adenine
3
Q
Purine synthesis needs
A
Glycine
Aspartate
Glutamine
4
Q
pyrimidine synthesis needs:
A
Aspartate
Glutamine (to make carbamoyl phosphate)
5
Q
ADA SCID mechanism
A
Cant turn Adenosine to Inosine, so all other base production is allosterically inhibited (ribonucleotide reductase)
6
Q
AA with one 1 codon
A
Methionine (AUG)
Tryptophan (UGG)
7
Q
DNA pol III vs pol I
A
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
Q
RT in humans
A
Telomerase (shortened telomere sin Bloom)
9
Q
mRNA read:
A
5’-3’
10
Q
Thing missing in these diseases:
- XP
- HNPCC
- FA, AT
A
- XP = NER
- HNPCC = MMR
- FA, AT = NHEJ
- BER for spontaneous/toxic deamination
11
Q
Phase of fixing stuff:
- NER
- BER
- MMR
A
- NER = G1
- BER = any
- MMR = G2
12
Q
fMET =
A
prok start codon
also PMN chemotaxis
13
Q
a-amantadin
A
inhibits RNA pol II (mRNA) and hepatotoxicity and nephrotoxicity
14
Q
rifampin vs actinomycinD
A
rifampin = proks dactinomycin = proks and euks
both inhibit RNA pols
15
Q
P-bodies
A
cytoplasmic mRNA QC
16
Q
CDK expression
A
constitutive but inactive until cyclin binds
17
Q
Golgi:
@ asparginine
@ serine
@ threonine
A
Asp = modificatoin of N-oligosaccharides Ser = addition of O-oligosaccharides Thre = addition of O-oligosarcharides
18
Q
mannose-6-P
A
for trafficking to lysosome
problem = 1-cell disease: coarse face, clouded cornea, restricted joint movements, high plasma lysosomal enzymes, fatal in childhood
19
Q
Peroxisome
A
VLCFS
BCFA
AA
20
Q
Prooteasome
A
mutations in Parkinsons
21
Q
Vimentin =
A
IF of messenchyme (CT)
22
Q
Desmin =
A
IF of muscle
23
Q
MT drugs:
A
Greisofulvin Paclitaxel Vincristine/vinblastine colchicine Mebendazole
24
Q
Ouabain
A
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)
