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Flashcards in biochem Deck (30)
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1

quinolones MOA

inhibits topoisomerase II (DNA gyrase) which inhibits DNA replication

2

Rifampin MOA

inhibits RNA polymerase which inhibits transcription

3

alpha-amanitin MOA

toxic substance in mushrooms that inhibits RNA Pol 2

4

Chloramphenicol MA

Peptidyl transferase, preventing peptide bond formation

5

Clindamycin MOA

Binds 50S large subunit, preventing translocation of ribosome

6

Macrolides MOA

Binds 50S large subunit, preventing translocation of ribosome

7

list macrolides

erythromycin, azithromycin

8

aminoglycosides MOA

Binds 30S small subunit, preventing initiation of translation

9

list aminoglycosides

Gentamicin, neomycin, and tobramycin

10

Tetracycline MOA

Binds 30S small subunit, preventing codon-anticodon pairing

11

mebendazole/thiabendazole MOA

inhibit microtubule synthesis in parasites

12

actinomycin D MOA

inhibits eukaryotic and prokaryotic transcription

13

cause of SCID

adenosine deaminase deficiency- buildup of ATP and dATP prevents DNA synthesis

14

Cause/ Sx of Lesch Nyhan syndrome

Defective purine salvage to to absent hypoxanthine-guanine phosphoribosyl transferase (which converts hypoxanthine to IMP and guanine to GMP). HGPRT: hyperuricemia, gout, pissed off (aggression, self mutilation), retardation, dystonia

15

xeroderma pigmentosum genetic defect

defective nucleotide excision repair of pyrimidine dimers

16

Hereditary non-polyposis colorectal cancer genetic defect

mismatch repair

17

ataxia telangiectasia gene defect

non-homologous end joining

18

inclusion dz- cause and Sx

inherited lysosomal storage disease (aka I cell disease). Defect in phosphotransferase > failure of golgi to phosphorylate mannose residues on glycoproteins > proteins are secreted extracellularly rather than delivered to lysosomes. Results in coarse facial features, clouded corneas, restricted joint movemnt, high plasma lysosomal enzyme levels. fatal in childhood

19

drugs that act on microtubules

"microtubules get constructed very poorly"- Mebendazole (anti-helminthes), griseofulvin (anti fungal), colchicine (anti gout), vincristine/vinblastine (anti cancer), paclitaxel (anti cancer)

20

Kartagener syndrome cause and sx

Immotile cilia due to dynein arm defect- results in male and female infertility due to immotile sperm and dysfunctional fallopian tube cilia. Also, bronchiectasis, recurrent sinusitis and situs inversus

21

list stains for intermediate filaments in CT, muscle, epithelial cells, neuroglia and neurons

Vimentin (CT), Desmin (muscle), cytokeratin (epithelial), GFAP (neuroglia), and neurofilaments (neurons)

22

cardiac glycosides- list, and MOA

digoxin and digitoxin- inhibit Na/K pump leading to elevated intracellular Na and inhibition o Na/Ca exchanger > elevated intracellular Ca leads to increased cardiac contractility

23

Osteogenesis imperfecta cause and Sx

decreased production of otherwise normal type I collagen due to problems forming triple helix (skin, bone, tendons). Fractures, blue sclera (translucent CT), hearing loss, lack of dentin in teeth

24

Ehlers Danlos- cause and Sx

hypermobility: decreased collagen type 1 (bone, skin, tendons). Vascular type: decreased collagen type 3 (blood vessels). Hyperextensible skin, easy bruising, berry and aortic aneurysms, organ rupture

25

Goodpasture cause

Abs against collagen type IV in basement membrane

26

Scurvy- what causes it

deficiency in Vit C leads to inability to hydroxylate proline and lysine, so collagen is weak

27

Menkes disease- cause and Sx

CT dz caused by impaired copper absorption and transport, leads to decreased activity of lysyl oxidase (Cu is cofactor). Results in brittle, kinky hair, growth retardation and hypotonia

28

Marfan syndrome cause

defect in fibrillin, a glycoprotein that forms a sheath around elastin

29

emphysema cause

alpha 1 antitrypsin deficiency- results in excess elastase activity

30

Southern vs Northern vs Western blots

SNW DRP: southern is DNA, Norhtern is RNA, western is protein