Term
| What are the 2 major contributors to energy difference between folded and denatured states? |
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Definition
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Term
| The energy of enthalpy during Protein stability comes from which forces? |
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Definition
Hydrophic forces
electrostatic forces
Hydrogen bonding |
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Term
| The energy of entropy during Proetin synthesis comes from what? |
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Definition
| from the difference of order between folded (highly ordered) and denatured (highly disordered) |
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Term
| What are the forces that stabilize protein structure? |
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Definition
Hydrophobic effect
Electrostatic interactions
van der Waals forces
H bonds
Chemical crosslinks |
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Term
| What is the thermodynamic hypothesis of protein folding? |
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Definition
| enough information in the amino acid sequence to favorably drive folding of native confirmation (adopted spontaneously) |
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Term
| What does Anfinsen's Experiment prove? |
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Definition
| proof that primary structure drives folding |
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Term
| What is Levinthal's paradox? |
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Definition
| The fact that proteins fold reliably and quickly to native state despite the myriad of potential conformations it can assume |
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Term
| Secondary protein structure formation has what effect on enthalpy and entropy? |
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Definition
Large negative effect on enthalpy (positive to drive folding)
small negative effect on entropy (negative for driving folding) |
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Term
| What is the effect on enthalpy and entropy of tertiary protein structure? |
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Definition
small negative enthalpy
high negative entropy |
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Term
| If secondary structure drives up negative enthalpy and tertiary structure drives up negative entropy (essentially a tie, energetically speaking), what causes the protein to actually fold? |
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Definition
| The folding, which exposes hydrophillic proteins to the aqueous system, increases the entropy of water [through hydrogen bonding]. This increase in disorder counters some of the decrease in disorder caused by the ordered protein folding |
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Term
| Why is the change in Gibbs energy marginal? |
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Definition
| This allows for proteins to be dynamic: can easily change from folded (and functional) to unfolded state dependent on physiological need |
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Term
| What is the 1st step of Protein Folding? |
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Definition
| collapse of flexible disordered unfolded poplypeptide chain into partially organized globular state. Called a molten globule |
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Term
| What is the second step of protein folding? |
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Definition
| native like elements of tertiary structure begin to form |
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Term
| What is the third and final step of protein folding? |
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Definition
| formation of native interactions throughout protein. Finally reaching the tertiary structure |
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Term
| What are the factors affecting protein folding and stability? |
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Definition
pH
Temperature
Detergent
Salts
Urea
Disulfide Bonds |
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Term
| True or False: The folded state of a protein is a single stable structure |
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Definition
| False: The native folded state of a protein exists in a series of rapidly interconverting and similar conformers |
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Term
| What are the three general classes of protein misfolding diseases? |
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Definition
1. impairment of folding efficiency of a protein results in reduction of protein
2. Misfolding of protein results in inproper traffiking of protein
3. Conversion of peptide or protein to fibrillar aggregates |
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