Term
| Sidechain-sidechain intermolecular interactions defines which level of protein structure? |
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Definition
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Term
| What is primary structure? |
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Definition
| The sequence of amino acids. |
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Term
| What does secondary structure consist of? |
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Definition
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Term
| What defines tertiary structure? |
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Definition
Side chain (hydrophobic and ionic) interactions. |
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Term
| What is the difference between tertiary and quaternary structure. |
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Definition
| Quaternary structure is comprised of two different polypeptides. |
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Term
| Which carbon in a polypeptide is flexible (can rotate)? |
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Definition
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Term
| What is the Φ angle looking towards? |
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Definition
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Term
| What is the Ψ angle looking toward? |
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Definition
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Term
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Definition
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Term
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Definition
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Term
In which region of the
Ramachandran plot would you find an amino acid in an α-helix? |
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Definition
| The lower left hand section around -90o,-60o. |
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Term
The secondary structure of some amino acids for any given protein will lie outside of the
allowed regions of the Ramachandran plot. Explain how this can happen. |
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Definition
| There will be some steric clash but it is possible for it to be there briefly. |
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Term
| Why are glycine and proline not found in secondary structures? |
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Definition
| Glycine has no stereochemistry because of the two hydrogens. Proline has a fixed Φ angle of 60o not allowing it to form angles necessary for secondary structure. |
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Term
Which face of an α-helix with the following sequence would interact with the nonpolar
binding site of a receptor protein? GVTSAIDTVLARGFTAYLAHG |
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Definition
| The face with nonpolar sidechains. |
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Term
| What level of protein structure is the coiled-coil |
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Definition
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Term
| What is the structure of α-keratin? |
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Definition
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Term
What thermodynamic considerations hold
the helices together? |
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Definition
| Nonpolar hydrophobic interactions. Increase entropy of water molecules. |
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Term
| What would a Glycine to Alanine mutation do to protein structure? |
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Definition
| Introduce a bump which would break up the london dispersion forces and allow water in. |
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Term
| What is the difference between random coil and irregular protein structure? |
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Definition
| Irregular structure would be loops while random coil would be the N-terminus or C-terminus. |
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