Lecture 5 - Peptides and Peptide Bonds Flashcards Preview

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Flashcards in Lecture 5 - Peptides and Peptide Bonds Deck (11):
0

Post-translational modifications of amino acids in proteins

Proteome

1

What transports amino acids to the ribosome?

tRNA molecules

2

Why is the peptide bond (bond between the carboxyl group of one amino acid and the amine group of another amino acid) short?

Because the C-N bond has some double bond character (40%) due to resonance with the C=O group.

3

Torsion angle between alpha C and N

Phi (φ)

4

Torsion angle from C=O to alpha C

Psi (ψ)

5

Torsion angle of the peptide bond

Omega (ω)

6

Which amino acid is found in the cis configuration?

Proline, due to its cyclical structure

7

How can you estimate the number of amino acid residues in a protein?

Dividing the molecular weight by 110

8

The number of peptide sequences possible is given by what formula?

(Number of possible AA's)^(peptide length)

9

Which nonpolar, aliphatic R group amino acid occurs the most in proteins?

Leucine (9.1%?)

10

Which aromatic R group amino acid occurs the least in proteins?

Tryptophan (1.4%)