Biochemistry Flashcards
Fabry dz
XLR; alpha-galactosidase; ceramide trihexoside; pw painful neuropathy, angiokeratomas, hypohydrosis; will develop progressive renal failure
Gauncher dz
AR; beta-glucocerebrosidase; glucocerebroside; gaucher cells (“crumpled tissue paper” macrophages), HSM, pancytopenia, severe bone and joint pain
Hurlur syndrome
AR; alpha-L-iduronidase; dermatan and heparan sulfate; gargoylism, developmental delay, corneal clouding, HSM
Hunter syndrome
XLR; iduronate sulfatase; dermatan and heparan sulfate; similar to, but milder than, Hurlur syndrome (no corneal clouding however)
Niemann-Pick dz
AR; sphingomyelinase; sphingomyelin; HSM, cherry-red spot in macula, foam cells, progressive neurodegeneration
TaySachs
AR; beta-hexosaminidase; Gm2 ganglioside; cherry-red spot in macula, progressive neurodegeneration, no HSM
Krabbe dz
AR; galactocerebrosidase; galactosylspingosine & galactocerebroside; progressive neurodegeneration, optic atrophy
Metachromatic leukodystrophy
AR; arylsulfatase A; cerebroside sulfate; muscle wasting, dementia, ataxia
Histones: AA?
lysine, arginine
In DNA methylation, which nucleotides are methylated?
cytosine and adenine
DNA methylation of what sequence represses transcription?
CpG islands
Histone methylation makes DNA what?
Mute
Histone acetylation makes DNA what?
Active
Uracil: made from what nucleotide, replaces what in RNA
Cytosine, thymine
Why does increased G-C content increase the melting temperature of DNA?
3 H bonds over 2
AA needed for purine synthesis (GAG)
Glycine, aspartate, glutamine
Adenosine deaminase deficiency MOA
Excess ATP and dATP imbalances nucleotide pool, prevent DNA synthesis and reduces lymphocyte count (cause autosomal recessive SCID)
Lesch-Nyhan syndrome MOA, pw
absent HGPRT leads to defective purine salvage (normally converts hypoxanthine to IMP and guanine to GMP). results in excess uric acid production and de novo purine synthesis; Hyperuricemia, Gout, Pissed off, Retardation, dysTonia
AUG
Methionine in eukoaryotes; fMet in prokaryotes (stimulates PMN chemotaxis)
non-degenerate AA
methionin (AUG), tryptophan (UGG)
DNA polymerase III
prokaryotic only; proofreads with 3’-5’ exonuclease
DNA polymerase I
degrades RNA primer and replaces it with DNA (5’-3’ exonuclease)
DNA ligase
catalyze the formation of phosphodiester bond within a strand of dsDNA (okazaki fragments)
telomerase
RNA-dependent DNA polymerase that adds DNA to 3’ ends of chromosomes to avoid loss of genetic material with every duplications, eukaryotes only