HOMEWORK 4
BIOL/CHEM 5310
due Tuesday, September 24, 2002

1. VVP text, Chapter 6, page 159, problems 1, 3

2. Explain why thestrength of an ionic interaction (ion pair) might be stronger if it is buried inside a protein, rather than on the aqueous surface.

3. Which of the following amino acids are more likely to be buried inside a protein?

a) His or Arg

b) Ser or Thr

c) Phe or Tyr

d) Ala or Val

4. How many hydrogen bonds exist in a 10-residue alpha helix, disregarding side chains and solvent? (See Chime image)

5. Examine the structure of Lysozyme (look at the Chime image).

a) Identify the secondary structure of residues 26-35
b) Identify the secondary structure motif of residues 42-53
c) Identify residue 54
d) Identify the residues in this turn. Which 2 oxygen atoms are 2.64 Å apart?

6. Identify the fibrous proteins that are known to contain significant amounts of the following amino acids:
a) Proline
b) Glycine
c) Cysteine

Last updated Monday, September 16, 2002

Comments/questions: svik@mail.smu.edu

Copyright 2002, Steven B. Vik, Southern Methodist University