biochem Flashcards
quinolones MOA
inhibits topoisomerase II (DNA gyrase) which inhibits DNA replication
Rifampin MOA
inhibits RNA polymerase which inhibits transcription
alpha-amanitin MOA
toxic substance in mushrooms that inhibits RNA Pol 2
Chloramphenicol MA
Peptidyl transferase, preventing peptide bond formation
Clindamycin MOA
Binds 50S large subunit, preventing translocation of ribosome
Macrolides MOA
Binds 50S large subunit, preventing translocation of ribosome
list macrolides
erythromycin, azithromycin
aminoglycosides MOA
Binds 30S small subunit, preventing initiation of translation
list aminoglycosides
Gentamicin, neomycin, and tobramycin
Tetracycline MOA
Binds 30S small subunit, preventing codon-anticodon pairing
mebendazole/thiabendazole MOA
inhibit microtubule synthesis in parasites
actinomycin D MOA
inhibits eukaryotic and prokaryotic transcription
cause of SCID
adenosine deaminase deficiency- buildup of ATP and dATP prevents DNA synthesis
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
xeroderma pigmentosum genetic defect
defective nucleotide excision repair of pyrimidine dimers
Hereditary non-polyposis colorectal cancer genetic defect
mismatch repair
ataxia telangiectasia gene defect
non-homologous end joining
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
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)
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
list stains for intermediate filaments in CT, muscle, epithelial cells, neuroglia and neurons
Vimentin (CT), Desmin (muscle), cytokeratin (epithelial), GFAP (neuroglia), and neurofilaments (neurons)
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
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
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
Goodpasture cause
Abs against collagen type IV in basement membrane
Scurvy- what causes it
deficiency in Vit C leads to inability to hydroxylate proline and lysine, so collagen is weak
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
Marfan syndrome cause
defect in fibrillin, a glycoprotein that forms a sheath around elastin
emphysema cause
alpha 1 antitrypsin deficiency- results in excess elastase activity
Southern vs Northern vs Western blots
SNW DRP: southern is DNA, Norhtern is RNA, western is protein
