| Qu 1: |
(a) Which of the following interactions is not an important
type of hydrogen bonding ? |
|
| -O-H ----O=C |
-N-H ----O=C |
-N-H ----O- |
-C-H ----O=C |
-N-H----N- |
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(i)
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(ii)
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(iii)
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(iv)
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(v)
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(b) Hydrogen bonding between pairs of amino acid residues is important
in the formation of peptide α-helices.
How many amino acid residues separate the pair ? |
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| Qu 2: |
Why doesn't methionine (see below) form disulfides ? |
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| Qu 3: |
(a) Why isn't protecting the amine group as a simple amide a good idea
in peptide synthesis ? |
|
(b) Why are esters good protecting groups for the carboxylic acid groups
in peptide synthesis ? |
|
(c) What 3 characteristics make a good protecting group ? |
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| Qu 4: |
What is meant by a term parallel when referring to β-sheets
in the secondary structure of peptides ? |
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| Qu 5: |
If the amino acids in peptides were the D-amino acids instead of L-amino
acids, what would be the implication for the structure of α-helices
? |
