SFM Quiz 2 Flashcards
(250 cards)
the storage site of lysosomal hydrolases No digestive events Homogenous Inactive enzymes
primary lysosomes
engaged in a catalytic process digestive enzymes heterogenous active enzymes
secondary lysosomes
Cholesterol uptake disrupted Characterized by elevation of LDL, the predominant cholesterol transport protein in the plasma
familial hypercholesteremia
absence or reduced number of peroxisomes congenital
Zellweger spectrum disorder
Binds to 30S subunit and interferes with the binding of fmet-tRNA and impairs initiation. Interferes with 30S subunit association with 50S subunit.
Streptomycin
binds to large 50S subunit, blocking translocation of the ribosome.
Clindamycin, Erythromycin
binds to small 30S subunit, blocks entry of aminoacyl-tRNA to ribosomal complex and impairs elongation.
Tetracycline
inhibits peptidyl transferase activity and impairs peptide bond formation.
Chloramphenicol
binds to large 60S subunit (euk.), blocking entry of aminoacyl-tRNA to ribosomal complex.
Shiga toxin, Ricin
inactivates GTP-bound EF-2, interfering with ribosomal translocation (euk.)
Diptheria toxin
inhibits peptidyl transferase (euk.) and impairs peptide bond formation.
Cycloheximide
causes premature chain termination (prok/euk). Resembles the 3’ end of the aminoacylated-tRNA. Enters the A site and adds to the growing chain. Forms a puromycylated chain, leading to premature chain release. More resistant to hydrolysis. Stops the ribosome from functioning.
Puromycin
does not change the amino acid.
silent mutation
changes amino acid in the protein with either no effect on protein function or a protein with vastly different function.
missense mutation
codon changes into a stop codon causing premature chain termination. Also called null mutation. Protein either degraded or formed as a truncated version.
nonsense mutation
one or more nucleotides are deleted or inserted into ORF. Out of frame causes change in the codon sequence and consequently alteration in the amino acid sequence of the protein (E.g., Duchenne Muscular Dystrophy, beta thalassemia)
frameshift mutation
Arises from a missense mutation of 6th codon in the allele of the gene for human β-globin (HBB),
Sickle cell anemia
Sickle cell anemia initial amino acid: Sickle cell anemia altered amino acid:
Glutamic acid Valine
out-of-frame (OOF) deletion to the dystrophin gene leads to partially or non-functioning dystrophin protein. leads to muscle wasting
Duchenne Muscular Dystrophy (DMD)
In-frame deletions result in expression of truncated forms of dystrophin, giving rise to a milder form of the disease
Becker muscular dystrophy
Translocation signal: cytoplasm
None
Translocation signal: Mitochondria
N-terminal hydrophobic alpha-helix HSP-70= chaperone through TOM->TIM->matrix
Translocation signal: Nucleus
KKKRK signal Nuclear pores
Translocation signal: Peroxisome
C-terminal SKL


















