Term
Where is info found for folding?
What controls the folding (not proteins)
Typical for what size of protein? |
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Definition
| In the primary structure of proteins. Thermodynamically controlled. typical for proteins <100 |
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Term
What drives side chain folding?
What happens when its driven?
How was it proven? |
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Definition
| Hydrophobicity drives and compacts protein. Polar groups get packed inwards, cant interact with water. Proven by only polar amino acid chains cant fold. |
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Term
| What did levinthal prove? |
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Definition
| Proteins cant fold randomly, not enough time in universe. |
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Term
| What is the foldon concept? |
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Definition
| sections of protein fold and act as a template for other parts to fold |
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Term
| What competes with protein folding? |
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Definition
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Term
| What does concentration favor? |
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Definition
| Concentration favors aggregation of protein rather than folding. |
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Term
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Definition
| macromolecules being crowded by other molecules, which limites their space and they act like they are in higher concentration |
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Term
| Excluded volume effect due to crowding causes what? |
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Definition
| effective concentration is higher, association rate constatnts of larger molecules increase, solubility goes down, rate of aggregation goes up. |
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Term
| Aggregation: Competes with? puts what at risk during translation? What is special about nuclear proteins? |
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Definition
| Folding, puts nascent chains at risk, and negative DNA interacts with positive histones which can cause aggregation. |
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Term
| Why are mutant proteins bad? |
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Definition
| Foldon sequence not working well, could take more time, more time for aggregation. Mutations can cause aggregation themselves. |
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Term
| What do foldases do? 2 types? |
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Definition
| catalyze proper folding? peptidyl-propyl cis trans isomerase (PPI), and Protein disulfide isomerase (PDI). |
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Term
| PPI. What stands for? What does it do? |
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Definition
| peptidyl-probly cis trans isomerase. catalyzes isomerization of protines, acts on proline residue to convert from trans to cis |
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Term
| PDI. What stands for? What does it do? In what family? |
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Definition
| protein disulfide isomerase. Oxidizes proteins quickly as compared to invitro which is slow. Catalyzes disulfife interchange reacctions, faciliites formation and shuffling of protein disulfides. In thioredoxin superfamily. |
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Term
| Molecular chaperones? What do they do? allow proteins to do what? |
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Definition
| prevent and correct interactions, like aggregation or wrong folding. Allow proteins to fold and assemble in a crowded enviornment in a fast way. |
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Term
| Are chaperones permanent? |
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Definition
| No, they leave once folded. |
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Term
| Structure of molecular chaperones? |
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Definition
| large diverse groups, non-covalent interaction, sometimes use ATP. |
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Term
| low MW chaperones, examples? What do they do? |
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Definition
| Hsp70, Hsp40, papD, prefoldin. Bind to hydrophobic sections until protein gets folded. Do not affect conformation |
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Term
| High MW. Examples? How do they act? |
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Definition
| GroEl, TriC. Cage principle, sequester proteins so they can fold away from others. |
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Term
| What can a mutation cause? |
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Definition
| aggregated protein, gain of too much stability and not let protein be changed or folded, can gain toxicity. |
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Term
| What can incomplete folding cause? |
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Definition
| loses function, loses stability, degrades. |
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Term
| Cystic fibrosis: Caused by? 70% have what? What protein affected? What happens? Aggregation or misfolding? |
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Definition
| Genetic mutation. 70% have deletion of phenylalanine at 508. Protein CFTR, misfolded. Cant transport NaCl out of cell so raised infection, blocks digestion by blocking pancreatic ducts, lowers nutritional uptake. |
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Term
| Lissencephaly (smooth brain) what happens? Caused by? |
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Definition
| Does not let neurons migrate well. lower tubulin function or certain microtubule function. R264T tubulin missnse affects chaperone mediated folding. Does not affect tubulin, but affects the chaperone. |
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Term
| Amyloidoses. What type of disease? how do they work? |
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Definition
| Aggregation disease. Dominated by beta sheet structure. gains toxicity. |
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Term
| A-1 antitrypsin deficiency. Due to? what happens? Where happens? |
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Definition
| misfolding or aggregation. loss of normal protease inhibitor. Aggregates in liver, causing damage. Lack of protein in lungs causing damage by neutrophil elastase. |
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Term
| Prion disease. Caused by? associated with? |
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Definition
| Infection of previously misfolded proteins, they act as a template for properply folded proteins and misfolds them. Associated with transmissable spongiform encephalopathy. |
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