pack Flashcards
What is a folded protein?
A folded protein is a functional protein
Is the process of protein folding random?
NO, it is an active process that isn’t random.
What is the function of chaperone?
Promote protein folding
and
Prevent protein misfolding and aggeregation.
How does chaperone promote protein folding? How does it prevent misfolding?
Folding:It binds to unfolded proteins using atp, after the atp is hydrolyzed, it releases folded (native) protein
Protection: shields out bad influnces
What is melting temperature of proteins?
T m is the temperature at which 50%
of the protein is unfolded
What is the typical melting temp for proteins?
Typical T m = 40-60 o C for proteins
What is denaturation?
unfolding and distruption of the secondary and tertiary structure without hydrolysis of peptide bonds
Can a denatured protein usually recover?
NO, they usually remain unfolded
Why is the aggregation of misfolded proteins a bad thing?
Bc they are very stable so too big to break down and too big to transport, and they become toxic.
What causes protein misfolding?
What is the molecule that is formed from aggregating proteins called?
Amyloid
What is amyloidosis?
a disease that
occurs when amyloid builds up in organs
What is an example of a disease that is caused by amloydosis?
alzheimer and parkinsons disease
What causes alzheimers?
An abnormal cleavage by secretase enzyme of the amyloid precursor protein which forms amyloid b-pleated sheets.
What protein forms the amyloid plaques in alzheimer?
amyloid β (Aβ) protein
What protien that is misfolded causes parkinsons disease?
Misfolding of alpha-synuclein (sy like see you bc the nuclei of the brain dissapear) (alpha wolves park in misfolded dens)
How are Prion Diseases caused?
Infectious abnormal prion (PrP sc) (sc = scrapie) interacts with a normal prion (PrP c) (c = cellular) altering its 3rd formation and changing it into an abnormal prion
What causes Transmissible spongiform encephalopathies?
infectious prions
What is the Transmissible spongiform encephalopathies called in humans?
Creutzfelt-Jacob disease (bc the affected can feel cruel bc of personality changes)
What is the Transmissible spongiform encephalopathies called in sheep?
Scrapie (bc you scrape them بتجمعهم in the herd)
What is the Transmissible spongiform encephalopathies called in cows?
Bovine Spongiform Encephalopathy (mad cow disease) (bc cows can be funny so they put them on vine)
What is HSP70?
Heat shock protein (chaperone) that promotes protein folding and fixes misfolded proteins due to stressful conditions
what is special about taq dna
has high melting temp and is used to amplify dna
What causes huntington disease?
An abnormal polyglutamine (CAG) repeat in the huntington protein which causes aggregation and in turn neuron death.
(bc the hunter needs a long and large rifle )
Why are protein aggregates so stable?
bc the hydrophobic parts are getting hidden so it misfolds and becomes stable
(like hemoglobin S)
What is another protein that causes Alzehimer?
Tau protein which gets hyperphosphorylated causing it to deattach from microtubules and form aggregates.
(old people like tahoes) (tahoes aggregates to you in the highway)
What protein causes cardiac amyloid?
Misfolding of transthyretin causing amyloids. (transport)
